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Achondroplasia
An autosomal dominant disorder that is the most frequent form of short-limb dwarfism. Affected individuals exhibit short stature caused by rhizomelic shortening of the limbs, characteristic facies with frontal bossing and mid-face hypoplasia, exaggerated lumbar lordosis, limitation of elbow extension, genu varum, and trident hand. Achondroplasia is the most common of the many types of short-limbed dwarfism. Achondroplasia is characterised by abnormal bone growth that results in short stature with disproportionately short arms and legs, a large head, and characteristic facial features. Intelligence and life span are usually normal, although an increased risk is present for death in infancy from compression of the spinal cord and/or upper airway obstruction. Achondroplasia is the most common form of inherited disproportionate short stature. It occurs in one in 15,000 to one in 40,000 live births. 
  In infancy, mild to moderate hypotonia is usual, and acquisition of developmental motor milestones is often delayed. Infants have difficulty in supporting their heads due to both hypotonia and large head size. True megalencephaly occurs in individuals with achondroplasia, but intelligence is normal unless hydrocephalus or other central nervous system complications occur. The large head of the newborn with achondroplasia creates an increased risk of intracranial bleeding during vaginal delivery . Hydrocephalus may be caused by increased intracranial venous pressure due to stenosis of the sigmoid sinus at the level of the narrowed jugular foramina. Recurring otitis media is frequently a problem. As many as 7.5% of infants with achondroplasia die in the first year of life from obstructive apnea or central apnea. 
  Recommendations for management of children with achondroplasia include:
    Monitoring height, weight, and head circumference using growth curves standardised for achondroplasia 
    Measures to avoid obesity starting in early childhood 
    Careful neurological examinations, with referral to a paediatric neurologist as necessary 
    MRI or CT of the foramen magnum region for evaluation of severe hypotonia or signs of spinal cord compression 
    Obtaining history for possible sleep apnea, with sleep studies as necessary 
    Evaluation for low thoracic or high lumbar gibbus if truncal weakness is present 
    Referral to a paediatric orthopaedist if bowing of the legs interferes with walking 
    Management of frequent middle ear infections 
    Speech evaluation by two years of age 
    Careful monitoring of social adjustment 

AIDS
An acquired defect of cellular immunity associated with infection by the human immunodeficiency virus (HIV), a CD4-positive T-lymphocyte count under 200 cells/microliter or less than 14% of total lymphocytes, and increased susceptibility to opportunistic infections and malignant neoplasms (tumors). Clinical manifestations also include emaciation (wasting) and dementia. These elements reflect criteria for AIDS as defined by the CDC in 1993.

Anemia
A reduction in the number of circulating erythrocytes (red blool cells) or in the quantity of hemoglobin.

Anorexia Nervosa
Syndrome in which the primary features include excessive fear of becoming overweight, body image disturbance, significant weight loss, refusal to maintain minimal normal weight, and amenorrhea. This disorder occurs most frequently in adolescent females.

Anxiety Disorders
Anxiety is considered abnormal when it occurs in situations that most people can deal with, without too much difficulty. Anxiety disorders refers to a wide range of disorders where anxiety is the main symptom ( Generalised anxiety and panic disorders ) or is experienced when the individual attempts to control certain maladaptive behaviours ( phobias and obsessive-compulsive disorder ).  Post-traumatic stress disorder is another anxiety disorder, which involves anxiety following a traumatic event. 
Separation anxiety also comes under this group of disorders. Anxiety disorders are the most common mental health problems that occur in children and adolescents. According to one large-scale study of 9 to 17 year olds, as many as 13% of young people had an anxiety disorder in a year.
  Symptoms and Signs.
    Generalised Anxiety Disorder . Symptoms include exaggerated worry and tension over everyday events. 
    Obsessive-Compulsive Disorder ( OCD ). Characterised by intrusive, unwanted, repetitive thoughts and rituals performed out of a feeling of urgent need; at least one-third of adult cases begins in childhood. 
    Panic Disorder . Characterised by feelings of extreme fear and dread that strike unexpectedly and repeatedly for no apparent reason, often accompanied by intense physical symptoms, such as chest pain, pounding heart, shortness of breath, dizziness, or abdominal distress. 
    Post-Traumatic Stress Disorder (PTSD). A condition that can occur after exposure to a terrifying event, most often characterised by the repeated re-experience of the ordeal in the form of frightening, intrusive memories, and brings on hypervigilance and deadening of normal emotions. 
    Phobias . 2 types: 
    1. Social phobia , extreme fear of embarrassment or being scrutinised; 
    2. Specific phobia , excessive fear of an object or situation, such as dogs, heights, loud sounds, flying, costumed characters, enclosed spaces, etc. 
    Other . Other anxiety disorders include: 
    Separation anxiety , excessive anxiety concerning separation from the home or from those to whom the person is most attached. Some degree of separation anxiety is normal and occurs in almost all children, especially in infants and toddlers. In contrast, separation anxiety disorder is excessive anxiety that goes beyond that expected for the child's developmental level. Some life stress, such as the death of a relative, friend, or pet or a geographic move or change in schools, usually triggers the disorder. 
    Selective mutism , persistent failure to speak in specific social situations. 
  Diagnosis and Treatment. Various forms of psychotherapy , including cognitive-behavioral therapy and family therapy, as well as certain medications, particularly selective serotonin re-uptake inhibitors (SSRIs), are used to treat anxiety disorders in children and adolescents. Research on the safety and efficacy of these treatments is ongoing. 

Aphasia
Loss or impairment of the power to use or comprehend words usually resulting from brain damage. A cognitive disorder marked by an impaired ability to comprehend or express language in its written or spoken form. This condition is caused by diseases which affect the language areas of the dominant hemisphere. Clinical features are used to classify the various subtypes of this condition. General categories include receptive, expressive, and mixed forms of aphasia.

Arthrogryposis
Persistent flexure or contracture of a joint.
  Arthrogryposis (Arthrogryposis Multiplex Congenita) is a term describing the presence of a muscle disorder that causes multiple joint contractures at birth. A contracture is a limitation in the range of motion of a joint. In most cases, arthrogryposis is not a genetic condition and does not occur more than once in a family. In about 30% of the cases, a genetic cause can be identified. The risk of recurrence for these cases varies with the type of genetic disorder. In some cases, few joints may be affected and the range of motion may be nearly normal. In the "classic" case of arthrogryposis, hands, wrists, elbows, shoulders, hips, feet and knees are affected. In the most severe cases, nearly every body joint may be involved, including the jaw and back. Frequently, the contractures are accompanied by muscle weakness, which further limits movement. Arthrogryposis is relatively rare, occurring in approximately one in 3,000 births.
Research has shown that anything that prevents normal joint movement before birth can result in joint contractures. The joint itself may be normal. However, when a joint is not moved for a period of time, extra connective tissue tends to grow around it, fixing it in position. Lack of joint movement also means that tendons connecting to the joint are not stretched to their normal length; short tendons, in turn, make normal joint movement difficult. (This same kind of problem can develop after birth in joints that are immobilized for long periods of time in casts.) 
  In general, there are four causes for limitation of joint movement before birth: 
    1. Muscles do not develop properly (atrophy). In most cases, the specific cause for muscular atrophy cannot be identified. Suspected causes include muscle diseases (for example, congenital muscular dystrophies), maternal fever during pregnancy, and viruses, which may damage cells that transmit nerve impulses to the muscles. 
    2. There is not sufficient room in the uterus for normal movement. For example, the mother may lack a normal amount of amniotic fluid, or have an abnormally shaped uterus. 
    3. Central nervous system and spinal cord are malformed. In these cases, a wide range of other conditions usually accompanies arthrogryposis. 
  4. Tendons, bones, joints or joint linings may develop abnormally. For example, tendons may not be connected to the proper place in a joint. 
  For most types of arthrogryposis, physical therapy has proven very beneficial in improving the range of motion of affected joints. Parents are encouraged to become active participants in a therapy program and to continue therapy at home on a daily basis. Splints can be made to augment the stretching exercises to increase range of motion. Casting is often used to improve foot position. However, emphasis should be placed on achieving as much joint mobility as possible. Some type of removable splint (perhaps a bi-valve cast) may be used on knees and feet so that the joints can be moved the muscled exercises periodically. In som cases, merely wearing a splint at night may be sufficient. Surgery may be used to treat the congenital deformities that frequently occur in conjunction with arthrogryposis or should be viewed as a supportive measure once physical therapy has achived maximum results but more range of motion is needed. Surgeries are commonly performed on feet, knees, hips, elbows and wrists to achieve better position or greater range of motion. In some cases, tendon transfers have been done to improve muscle function. Congenital deformities of the feet, hips and spine may require surgical correction at or about one year of age. There is a wide variation in the degree to which muscles and joints are affected in those with arthrogryposis. In some cases, arthrogryposis may be accompanied by other conditions, such as central nervous system disorders, which complicate the picture. However, in most cases, the outlook for those with arthrogryposis is a positive one. Unlike many other conditions, arthrogryposis is non-progressive; it does not worsen with age. Furthermore, with physical therapy and other available treatments, substantial improvement in function is usually possible. Most people with arthrogryposis are of normal intelligence and are able to lead productive, independent lives as adults. 

Asthma
A form of bronchial disorder associated with airway obstruction, marked by recurrent attacks of  difficult or labored respiration, with wheezing due to spasmodic contraction of the bronchi. 

Ataxia
Impairment of the ability to perform smoothly coordinated voluntary movements. This condition may affect the limbs, trunk, eyes, pharnyx, larnyx, and other structures. Ataxia may result from impaired sensory or motor function. Sensory ataxia may result from posterior column injury or PERIPHERAL NERVE DISEASES. Motor ataxia may be associated with CEREBELLAR DISEASES; CEREBRAL CORTEX diseases; THALAMIC DISEASES; BASAL GANGLIA DISEASES; injury to the mid-brian; and other conditions.

Athetosis
A dyskinesia characterized by an inability to maintain the fingers, toes, tongue, or other body parts in a stable position, resulting in continuous slow, sinusoidal, snake-like, and flowing involuntary movements. This condition is frequently accompanied by CHOREA, where it is referred to as choreoathetosis. Athetosis may occur as a manifestation of BASAL GANGLIA DISEASES or DRUG TOXICITY, NERVOUS SYSTEM.

Attention Deficit Disorder (ADD) / Attention Deficit Disorder with Hyperactivity (ADDHD)
A behavior disorder originating in childhood in which the essential features are signs of developmentally inappropriate inattention, impulsivity, and hyperactivity. Although most individuals have symptoms of both inattention and hyperactivity-impulsivity, one or the other pattern may be predominant. The disorder is more frequent in males than females. Onset is in childhood. Symptoms often attenuate during late adolescence although a minority experience the full complement of symptoms into mid-adulthood.

Autism
A disorder beginning in childhood. It is marked by the presence of markedly abnormal or impaired development in social interaction and communication and a markedly restricted repertoire of activity and interest. Manifestations of the disorder vary greatly depending on the developmental level and chronological age of the individual.  AKA - "mind blindness"

Bipolar Disorder / Manic-Depressive Illness
Although rare in young children, bipolar disorder , or manic-depressive illness , can appear in both children and adolescents. Bipolar disorder, which involves unusual shifts in mood, energy, and functioning, may begin with either manic, depressive, or mixed manic and depressive symptoms. It is more likely to affect the children of parents who have the disorder. 20 to 40% of adolescents with major depression develop bipolar disorder within 5 years after depression onset. 
Existing evidence indicates that bipolar disorder beginning in childhood or early adolescence may be a different, possibly more severe form of the illness than older adolescent- and adult-onset bipolar disorder. When the illness begins before or soon after puberty, it is often characterised by a continuous, rapid-cycling, irritable, and mixed symptom state that may co-occur with disruptive behaviour disorders, particularly attention deficit hyperactivity disorder (ADHD) or conduct disorder , or may have features of these disorders as initial symptoms. 

Blind
Persons with loss of vision such that there is an impact on activities of daily living.

Blindness
The inability to see or the loss or absence of perception of visual stimuli. This condition may be the result of EYE DISEASES; OPTIC NERVE DISEASES; OPTIC CHIASM diseases; or BRAIN DISEASES affecting the VISUAL PATHWAYS or OCCIPITAL LOBE.
  Types - Legal, Complete, Hysterical, Monocular, Partial, Transient
  Blindness, Acquired Word
A receptive visual aphasia characterized by the loss of a previously possessed ability to comprehend the meaning or significance of handwritten words, despite intact vision. This condition may be associated with posterior cerebral artery infarction (INFARCTION, POSTERIOR CEREBRAL ARTERY) and other BRAIN DISEASES.
  Blindness, Color
Defects of color vision are mainly hereditary traits but can be secondary to acquired or developmental abnormalities in the CONES (RETINA). Severity of hereditary defects of color vision depends on the degree of mutation of the OPSIN genes (on X CHROMOSOME and CHROMOSOME 3, HUMAN) that code the photopigments for red, green and blue.
  Blindness, Cortical
Total loss of vision in all or part of the visual field due to bilateral OCCIPITAL LOBE (i.e., VISUAL CORTEX) damage or dysfunction. Anton syndrome is characterized by the psychic denial of true, organic cortical blindness.
  Blindness, Day - Visual impairments limiting one or more of the basic functions of the eye: visual acuity, dark adaptation, color vision, or peripheral vision. Visual disability refers to inability of the individual to perform specific visual tasks, such as reading, writing, orientation, or traveling unaided.
  Blindness, Night
Failure or imperfection of vision at night or in dim light, with good vision only on bright days.
  Blindness, Pure Word 
Loss of the power to comprehend written materials despite preservation of the ability to write (i.e., alexia without agraphia). This condition is generally attributed to lesions that "disconnect" the visual cortex of the non-dominant hemisphere from language centers in the dominant hemisphere. This may occur when a dominant visual cortex injury is combined with underlying white matter lesions that involve crossing fibers from the occipital lobe of the opposite hemisphere. 
  Blindness, Word
A cognitive disorder characterized by an impaired ability to comprehend written and printed words or phrases despite intact vision. This condition may be developmental or acquired. Developmental dyslexia is marked by reading achievement that falls substantially below that expected given the individual's chronological age, measured intelligence, and age-appropriate education. The disturbance in reading significantly interferes with academic achievement or with activities of daily living that require reading skills.

Bulimia Nervosa
Episodic binge eating. The episodes may be associated with the fear of not being able to stop eating, depressed mood, or self-deprecating thoughts (binge-eating disorder) and may frequently be terminated by self-induced vomiting (bulimia nervosa).

Cancer
New abnormal growth of tissue. Malignant neoplasms (tumors) show a greater degree of anaplasia (loss of structural differentiation and useful function of neoplastic cells) and have the properties of invasion and metastasis, compared to benign neoplasms.

Catatonia (catatonic)
A neuropsychiatric disorder characterized by one or more of the following essential features: immobility, mutism, negativism (active or passive refusal to follow commands), mannerisms, stereotypies, posturing, grimacing, excitement, echolalia, echopraxia, muscular rigidity, and stupor; sometimes punctuated by sudden violent outbursts, panic, or hallucinations. This condition may be associated with psychiatric illnesses (e.g., SCHIZOPHRENIA; MOOD DISORDERS) or organic disorders (NEUROLEPTIC MALIGNANT SYNDROME; ENCEPHALITIS, etc.).

Cerebral Palsy
A condition which is characterized by a lack of voluntary motor control - it may be congenital or it may be caused by an injury to the cerebrum.
  A heterogeneous group of nonprogressive motor disorders caused by chronic brain injuries that originate in the prenatal period, perinatal period, or first few years of life. The four major subtypes are spastic, athetoid, ataxic, and mixed cerebral palsy, with spastic forms being the most common. The motor disorder may range from difficulties with fine motor control to severe spasticity (see MUSCLE SPASTICITY) in all limbs. Spastic diplegia (Little disease) is the most common subtype, and is characterized by spasticity that is more prominent in the legs than in the arms.
Cerebral Palsy, Athetosis
Cerebral Palsy, Athetoid
Cerebral Palsy, Atonic
Cerebral Palsy, Congenital
Cerebral Palsy, Hemiplegic
Cerebral Palsy, Diplegic, Infantile
Cerebral Palsy, Dyskinetic
Cerebral Palsy, Dystonic Rigid
Cerebral Palsy, Dystonic-Rigid
Cerebral Palsy, Hypotonic
Cerebral Palsy, Mixed
Cerebral Palsy, Monoplegic
Cerebral Palsy, Monoplegic, Infantile
Cerebral Palsy, Quadriplegic, Infantile
Cerebral Palsy, Rolandic Type
Cerebral Palsy, Spastic

Cervical Spinal Cord Injury
Injury of or relating to a neck and the spine or the spinal or vertebral column in the neck.  Cervical spinal cord injury is associated with quadriplegia.

Chondromalacia of Patella (runner's knee)
This disorder is characterized by well-localized pain when the patella is grated against the femoral condyles or when the knee is actively extended with the patella manually displaced distally. The association of patellar chondromalacia with recurrent dislocation of the patella is well known.  Patellar chondromalacia former is usually attributed to the recurrent dislocation of the patella. However, the cause and effect relation may be the other way around, in some cases. This condition is probably not a form of osteochondritis dissecans, which can affect the patella. - This disease is also known as softening of the cartilage of your knee cap or "anterior knee pain". This is a big medical word for a condition where the shiny cartilage surface of your patella (knee cap) is softened due to many factors including abnormal pressure across the joint surface or hormonal changes in your body.  
  This pain is usually located over the front of the knee and is described as a deep aching pain. It is sometimes associated with swelling and is usually worse when the knee is bent for long periods of time such sitting in a car or bus. The pain is also worse with such activities as squatting, kneeling or stair climbing (either up or down stairs). The pain is sometimes improved with rest and the use of pain medication. It is sometimes associated with mild or moderate swelling of the knee and some people report a grinding feeling in their kneecap. It is more common in younger females especially after a growth spurt where the knee must carry more weight. Many times this problem can be due to "excess lateral pressure syndrome" - that is, the kneecap tending to sit too far out to the side of the knee. Usually, this problem is related to how one's bones are shaped and determined by genetics. In this case, the kneecap is most tender when pushing on its outside ("lateral") surface. It is usually pretty simple to diagnose chondromalacia. Mostly it is diagnosed based on the patient's complaints. On physical examination, the doctor may push back on the kneecap - that often causes pain in people with this problem. Chondromalacia patella is the most common cause of pain in the front of the knee.  Many doctors recommend that patients with chondromalacia perform low-impact exercises that strengthen muscles, particularly the inner part of the quadriceps, without injuring joints. Swimming, riding a stationary bicycle, and using a cross-country ski machine are acceptable as long as the knee is not bent more than 90 degrees. Electrical stimulation may also be used to strengthen the muscles. If these treatments fail to improve the condition, the physician may perform arthroscopic surgery to smooth the surface of the articular cartilage and wash out” cartilage fragments that cause the joint to catch during bending and straightening. In more severe cases of chondromalacia, surgery may be necessary to correct the angle of the kneecap and relieve friction involving the cartilage or to reposition parts that are out of alignment.

Chorea
Involuntary, forcible, rapid, jerky movements that may be subtle or become confluent, markedly altering normal patterns of movement. Hypotonia and pendular reflexes are often associated. Conditions which feature recurrent or persistent episodes of chorea as a primary manifestation of disease are referred to as CHOREATIC DISORDERS. Chorea is also a frequent manifestation of BASAL GANGLIA DISEASES.

Chronic Fatigue Disorder
A syndrome characterized by persistent or recurrent fatigue, diffuse musculoskeletal pain, sleep disturbances, and subjective cognitive impairment of 6 months duration or longer. Symptoms are not caused by ongoing exertion; are not relieved by rest; and result in a substantial reduction of previous levels of occupational, educational, social, or personal activities. Minor alterations of immune, neuroendocrine, and autonomic function may be associated with this syndrome. There is also considerable overlap between this condition and FIBROMYALGIA.

Conduct Disorder
The term conduct disorder refers to a complicated group of behavioural and emotional problems in youngsters. Children and adolescents with this disorder have great difficulty following rules and behaving in a socially acceptable way. They are often viewed by other children, adults and social agencies as bad or delinquent, rather than mentally ill. Many factors may contribute to a child developing conduct disorder, including brain damage, child abuse, genetic vulnerability, school failure, and traumatic life experiences.  
  Symptoms and Signs. Children or adolescents with conduct disorder may exhibit some of the following behaviours: 
  Aggression towards people and animals: including bullying; intimidation; use of a weapon; physical cruelty; etc. 
  Destruction of Property: including, for example, deliberately engaged in fire setting with the intention to cause damage and deliberately destroying other's property. 
  Deceitfulness, lying, or stealing. 
  Serious violations of rules: e.g. truancy; runs away from home; stays out at night despite parental objections. 
  Diagnosis and Treatment. Children who exhibit these behaviours should receive a comprehensive evaluation. Many children with a conduct disorder may have coexisting conditions such as mood disorders , anxiety , Post-Traumatic Stress Disorder , substance abuse, ADHD , learning problems, or thought disorders which can also be treated. Research shows that youngsters with conduct disorder are likely to have ongoing problems if they and their families do not receive early and comprehensive treatment. Without treatment, many youngsters with conduct disorder are unable to adapt to the demands of adulthood and continue to have problems with relationships and holding a job. They often break laws or behave in an antisocial manner. Treatment of children with conduct disorder can be complex and challenging. Treatment can be provided in a variety of different settings depending on the severity of the behaviours. Adding to the challenge of treatment are the child's uncooperative attitude, fear and distrust of adults. In developing a comprehensive treatment plan, a child and adolescent psychiatrist may use information from the child, family, teachers, and other medical specialities to understand the causes of the disorder. Behaviour therapy and psychotherapy are usually necessary to help the child appropriately express and control anger. Special education may be needed for youngsters with learning disabilities. Parents often need expert assistance in devising and carrying out special management and educational programs in the home and at school. Treatment may also include medication in some youngsters, such as those with difficulty paying attention, impulse problems, or those with depression. Treatment is rarely brief since establishing new attitudes and behaviour patterns takes time. However, early treatment offers a child a better chance for considerable improvement and hope for a more successful future. 

Cystic Fibrosis
An inherited disease that causes the body to produce mucus that's extremely thick and sticky. This mucus clogs passages in many of the body's organs (including the lungs, the liver, the pancreas, the sweat glands, and the reproductive organs). It mainly affects the lungs and the pancreas, causing serious problems with respiration, digestion and excretion.
  An inherited disease of exocrine glands, affecting most characteristically the pancreas, respiratory system, and sweat glands, usually beginning in infancy and typified by chronic respiratory infections, pancreatic insufficiency, and susceptibility to heat prostration. Cirrhosis of liver occurring in childhood is common and may produce portal hypertension, splenomegaly, and hypersplenism.

Deafness
A general term for the complete or partial loss of the ability to hear from one or both ears. Deafness may result from EAR DISEASES; VESTIBULOCOCHLEAR NERVE DISEASES; or BRAIN DISEASES.
  postlingual - after learning to talk
  prelingual - before learning to talk

Diabetes (diabetes mellitus)
A heterogeneous group of disorders that share glucose intolerance in common. - a variable disorder of carbohydrate metabolism caused by a combination of hereditary and environmental factors and usually characterized by inadequate secretion or utilization of insulin, by excessive urine production, by excessive amounts of sugar in the blood and urine, and by thirst, hunger, and loss of weight.
  Type I Diabetes (Juvenile Diabetes / Insulin-Dependent Diabetes ) - a form of diabetes mellitus that usually develops during childhood or adolescence and is characterized by a severe deficiency in insulin secretion resulting from atrophy of the islets of Langerhans and causing hyperglycemia and a marked tendency towards ketoacidosis -- called also insulin-dependent diabetes, insulin-dependent diabetes mellitus 
  Type II Diabetes (Non-Insulin-Dependent Diabetes / Adult Onset Diabetes) - a common form of diabetes mellitus that develops especially in adults and most often in obese individuals and that is characterized by hyperglycemia resulting from impaired insulin utilization coupled with the body's inability to compensate with increased insulin production -- called also non-insulin-dependent diabetes, non-insulin-dependent diabetes mellitus, adult onset diabetes, adult onset diabetes mellitus

Dissociation (disassociation - to detach from association)
Sudden temporary alterations in the normally integrative functions of consciousness.  The separation of whole segments of the personality (as in multiple personality) or of discrete mental processes (as in the schizophrenias) from the mainstream of consciousness or of behavior

Distractibility
A general characteristic of developmental/learning diabilities where a person's attention is easy to divert or turn aside.  Distract : to draw or direct (as one's attention) to a different object or in different directions at the same time - to stir up or confuse with conflicting emotions or motives

Down Syndrome
A congenital birth defect that causes mental retardation and a characteristic facial appearance (i.e. Mongoloid - flat face and slanted eyes). It is closely associated with a tendency toward obesity and cardiac conditions. A chromosome disorder associated either with an extra chromosome 21 or an effective third chromosome 21. Clinical manifestations include hypotonia (deficient muscule tone or tension), short stature, short-headed or broad-headed , upslanting eyes, folds of the skin on eyelids, protruding tongue, small ears, short, broad hands, a somewhat Simian appearance, and moderate to severe MENTAL RETARDATION. Cardiac and gastrointestinal malformations, a marked increase in the incidence of LEUKEMIA, and the early onset of ALZHEIMER DISEASE are also associated with this condition.

Dyscalculia (or dyscalcula)
"Dyscalculia" is a lessor-known learning disability that affects mathatical calculations. It is derived from the generic name "mathematics difficulty". When a student's mathematics difficulties are severe enough to meet certain criteria, special education services are indicated. However, "dyscalculia" has no clearly defined criteria and cannot be assessed reliably. A student with any degree of mathematics difficulty may be considered to have "dyscalculia" by some educational specialists. Because of the ambiguity of categorization, being identified as having "dyscalculia" may or may not indicate the need for special education services. The term appears to be seldom used within public schools because of the lack of any clear, measurable criteria. Nevertheless, many students have it.  Dyscalculia has several underlying causes. One of the most prominent is a weakness in visual processing. To be successful in mathematics, one needs to be able to visualize numbers and mathematics situations. Students with dyscalculia have a very difficult time visualizing numbers and often mentally mix up the numbers, resulting in what appear to be "stupid mistakes."  Another problem is with sequencing. Students who have difficulty sequencing or organizing detailed information often have difficulty remembering specific facts and formulas for completing their mathematical calculations. 

Dysglossia
Acquired or developmental conditions marked by an impaired ability to comprehend or generate spoken forms of language.

Dysgraphia
Loss or impairment of the ability to write (letters, syllables, words, or phrases) due to an injury to a specific cerebral area or occasionally due to emotional factors. This condition rarely occurs in isolation, and often accompanies APHASIA.

Dyskinesia
Abnormal involuntary movements which primarily affect the extremities, trunk, or jaw that occur as a manifestation of an underlying disease process. Conditions which feature recurrent or persistent episodes of dyskinesia as a primary manifestation of disease may be referred to as dyskinesia syndromes (see MOVEMENT DISORDERS). Dyskinesias are also a relatively common manifestation of BASAL GANGLIA DISEASES.

Dyslexia
A cognitive disorder characterized by an impaired ability to comprehend written and printed words or phrases despite intact vision. This condition may be developmental or acquired. Developmental dyslexia is marked by reading achievement that falls substantially below that expected given the individual's chronological age, measured intelligence, and age-appropriate education. The disturbance in reading significantly interferes with academic achievement or with activities of daily living that require reading skills. 

Dyspraxia (Clumsy Child Syndrome)
A group of cognitive disorders characterized by the inability to perform previously learned skills that cannot be attributed to deficits of motor or sensory function. The two major subtypes of this condition are ideomotor (see APRAXIA, IDEOMOTOR) and ideational apraxia, which refers to loss of the ability to mentally formulate the processes involved with performing an action. For example, dressing apraxia may result from an inability to mentally formulate the act of placing clothes on the body. Apraxias are generally associated with lesions of the dominant PARIETAL LOBE and supramarginal gyrus.
  ‘Clumsy Child Syndrome’ or dyspraxia (which, in simple terms, means an inability to make skilled movements with accuracy). Clumsy child syndrome refers to a boy/girl who performs fine and/or gross motor tasks in an immature, disorganised, erratic, slow, irregular, or inconsistent fashion. The motor skills are imprecise rather than grossly impaired, and the neurologic examination does not show any significant abnormalities including involuntary movements or disabilities.   It is a disorder of the brain that results in the patient’s inability to organize movements rather than clumsiness due to weakness, loss of proper sensation or true disease of the brain.  These children may have cognitive or perceptual problems leading to learning disabilities as well. What causes this is not well understood.  Most children who have this syndrome have what is called dyspraxia. This is a fancy term which refers to volitional movements that are not done skillfully in spite of an intact sensory and motor nervous system. In other words, all the movements can be physically accomplished except for the fact that the coordination is off making completion of the task difficult. The dyspraxia can then be further classified into subtypes: 
  Ideomotor Dyspraxia. Inability to perform single motor tasks when requested to do so verbally or by visual imitation. Examples include combing hair or waving goodbye. 
  Ideational Dyspraxia. In contrast to ideomotor dyspraxia, the ideational dyspraxic child is capable of executing simple gestures in response to verbal commands but has difficulty executing a sequence of multistep motor tasks. The child cannot make a plan to complete the task. An example would be the child who given a toothbrush, toothpaste, and a cup is able to use each item individually but unable to complete brushing his teeth in the usual sequence. He may pour the water from the cup onto the toothbrush rather than apply the toothpaste, etc. 
  Dressing Dyspraxia. This is a subtype of ideational dyspraxia in which the difficulties center around donning articles of clothing. 
  Oromotor Dyspraxia. This interferes with speech. 
  Constructional Dyspraxia. This relates to difficulty with spatial relations. Inability to imitate block designs is an example.

Encephalitis
Inflammation of the BRAIN due to infection, autoimmune processes, toxins, and other conditions. Viral infections (see ENCEPHALITIS, VIRAL) are a relatively frequent cause of this condition.

Epilepsy
A disorder characterized by recurrent episodes, fits, attacks, or sudden increase or recurrence of symptoms of brain dysfunction due to a sudden, disorderly, and excessive neuronal discharge.  Epilepsy classification systems are generally based upon: (1) clinical features of the seizure episodes (e.g., motor seizure), (2) etiology (e.g., post-traumatic), (3) anatomic site of seizure origin (e.g., frontal lobe seizure), (4) tendency to spread to other structures in the brain, and (5) temporal patterns (e.g., nocturnal epilepsy).

Exercise Induced Asthma
A constriction of the bronchial tubes closely associated with physical exertion. - Asthma attacks following a period of exercise. Usually the induced attack is short-lived and regresses spontaneously. The magnitude of postexertional airway obstruction is strongly influenced by the environment in which exercise is performed (i.e. inhalation of cold air during physical exertion markedly augments the severity of the airway obstruction; conversely, warm humid air blunts or abolishes it).

Fasciculation
Involuntary contraction of the muscle fibers innervated by a motor unit. Fasciculations can often by visualized and take the form of a muscle twitch or dimpling under the skin, but usually do not generate sufficient force to move a limb. They may represent a benign condition or occur as a manifestation of MOTOR NEURON DISEASE or PERIPHERAL NERVOUS SYSTEM DISEASES.

Fibromyalgia
A common nonarticular rheumatic syndrome characterized by myalgia and multiple points of focal muscle tenderness to palpation (trigger points). Muscle pain is typically aggravated by inactivity or exposure to cold. This condition is often associated with general symptoms, such as sleep disturbances, fatigue, stiffness, HEADACHES, and occasionally DEPRESSION. There is significant overlap between fibromyalgia and the chronic fatigue syndrome (FATIGUE SYNDROME, CHRONIC). Fibromyalgia may arise as a primary or secondary disease process. It is most frequent in females aged 20 to 50 years. 

Genu Valgum (knock-knees)
A condition in which the legs curve inward at the knees.

Genu Varum (bowlegged)
Bowlegs is a condition observed when a person stands with the feet and ankles together, but the knees remain widely apart. 

Gerstmann's Syndrome 
This developmental learning disorder is characterized by:
Finger agnosia.....difficulty locating body parts in space 
Dyscalculia..........difficulty with mathematics 
Right-Left disorientation 
Dygraphia...difficulty in writing 

Grand Mal Seizure / Grand Mal Convulsion
A seizure/convulsion that is characterized by violent muscular contractions, convulsions, and unconsciousness. A generalized seizure disorder characterized by recurrent major motor seizures. The initial brief tonic phase is marked by trunk flexion followed by diffuse extension of the trunk and extremities. The clonic phase features rhythmic flexor contractions of the trunk and limbs, pupillary dilation, elevations of blood pressure and pulse, urinary incontinence, and tongue biting. This is followed by a profound state of depressed consciousness (post-ictal state) which gradually improves over minutes to hours. The disorder may be cryptogenic, familial, or symptomatic (caused by an identified disease process). 

Guillain Barre Syndrome
Guillain-Barré syndrome (GBS) causes progressive muscle weakness and paralysis (the complete inability to use a particular muscle or muscle group), which develops over days or up to four weeks, and lasts several weeks or even months. -   An acute inflammatory autoimmune neuritis caused by T cell- mediated cellular immune response directed towards peripheral myelin. Demyelination occurs in peripheral nerves and nerve roots. The process is often preceded by a viral or bacterial infection, surgery, immunization, lymphoma, or exposure to toxins. Common clinical manifestations include progressive weakness, loss of sensation, and loss of deep tendon reflexes. Weakness of respiratory muscles and autonomic dysfunction may occur.
  The cause of the weakness and paralysis of GBS is the loss of myelin, which is the material that coats nerve cells (the loss of myelin is called demyelination). Myelin is an insulating substance which is wrapped around nerves in the body, serving to speed conduction of nerve impulses. Without myelin, nerve conduction slows or stops. GBS has a short, severe course. It causes inflammation and destruction of the myelin sheath, and it disturbs multiple nerves. Therefore, it is considered an acute inflammatory demyelinating polyneuropathy.
  The reason for the destruction of myelin in GBS is unknown, although it is thought that the underlying problem is autoimmune in nature. An autoimmune disorder is one in which the body's immune system, trained to fight against such foreign invaders as viruses and bacteria, somehow becomes improperly programmed. The immune system becomes confused, and is not able to distinguish between foreign invaders and the body itself. Elements of the immune system are unleashed against areas of the body, resulting in damage and destruction. For some reason, in the case of GBS, the myelin sheath appears to become a target for the body's own immune system.
  The first symptoms of GBS consist of muscle weakness (legs first, then arms, then face), accompanied by prickly, tingling sensations (paresthesias). Symptoms affect both sides of the body simultaneously, a characteristic that helps distinguish GBS from other causes of weakness and paresthesias. Normal reflexes are first diminished, then lost. The weakness eventually affects all the voluntary muscles, resulting in paralysis. When those muscles necessary for breathing become paralyzed, the patient must be placed on a mechanical ventilator which takes over the function of breathing. This occurs about 30% of the time. Very severely ill GBS patients may have complications stemming from other nervous system abnormalities which can result in problems with fluid balance in the body, severely fluctuating blood pressure, and heart rhythm irregularities.

Hallux Valgus - (hammer toe)
Lateral displacement of the great toe, producing deformity of the first metatarsophalangeal joint with callous, bursa, or bunion formation over the bony prominence.
  Hallux Abductovalgus (abducted)
Lateral displacement of the great toe, producing deformity of the first metatarsophalangeal joint with callous, bursa, or bunion formation over the bony prominence.
  Hallux Limitus
A bony proliferation and articular degeneration of the first METATARSOPHALANGEAL JOINT that is characterized by pain and a progressive decrease in the dorsiflexion range of motion.
  Hallux Rigidus
A condition caused by degenerative arthritis (see OSTEOARTHRITIS) of the METATARSOPHALANGEAL JOINT of the great toe and characterized by pain and limited dorsiflexion, but relatively unrestricted plantar flexion.

Haptic Perception
Relating to or based on the sense of touch.

Heart Murmur - sounds that are made as the blood flows through a leaky heart valve
Abnormal heart sounds heard during auscultation caused by alterations in the flow of blood into a chamber, through a valve, or by a valve opening or closing abnormally. They are classified by the time of occurrence during the cardiac cycle, the duration, and the intensity of the sound on a scale of I to V.

Hemiplegia
Severe or complete loss of motor function on one side of the body. This condition is usually caused by BRAIN DISEASES that are localized to the cerebral hemisphere opposite to the side of weakness. Less frequently, BRAIN STEM lesions; cervical SPINAL CORD DISEASES; PERIPHERAL NERVOUS SYSTEM DISEASES; and other conditions may manifest as hemiplegia. The term hemiparesis (see PARESIS) refers to mild to moderate weakness involving one side of the body.

Hemophilia (free bleeder)
The classic hemophilia resulting from a deficiency of factor VIII. It is an inherited disorder of blood coagulation characterized by a permanent tendency to hemorrhage. 
  Factor VIII - Blood-coagulation factor VIII. Antihemophilic factor that is part of the factor VIII/von Willebrand factor complex. Factor VIII is produced in the liver and acts in the intrinsic pathway of blood coagulation. It serves as a cofactor in factor X activation and this action is markedly enhanced by small amounts of thrombin.

Hernia
Protrusion of a loop or knuckle of an organ or tissue through an abnormal opening.

HIV - HIV Disease
Human immunodeficiency virus.  It is acknowledged to be the agent responsible for the acute infectious manifestations, neurologic disorders, and immunologic abnormalities linked to the ACQUIRED IMMUNODEFICIENCY SYNDROME (AIDS).

Hydrocephalic / Hydrocephalus
an abnormal increase in the amount of cerebrospinal fluid within the cranial cavity that is accompanied by expansion of the cerebral ventricles, enlargement of the skull and especially the forehead, and atrophy of the brain. Excessive accumulation of cerebrospinal fluid within the cranium which may be associated with dilation of cerebral ventricles, INTRACRANIAL HYPERTENSION; HEADACHE; lethargy; URINARY INCONTINENCE; and ATAXIA (and in infants macrocephaly). This condition may be caused by obstruction of cerebrospinal fluid pathways due to neurologic abnormalities, INTRACRANIAL HEMORRHAGES; CENTRAL NERVOUS SYSTEM INFECTIONS; BRAIN NEOPLASMS; CRANIOCEREBRAL TRAUMA; and other conditions. 

Hyperactivity
The state or condition of being excessively or pathologically active. Especially associated with ATTENTION DEFICIT DISORDER.
  Hyperactivity, Motor
Excessive movement of muscles of the body as a whole, which may be associated with organic or psychological disorders.
  Hyperactivity, Psychomotor
A feeling of restlessness associated with increased motor activity. This may occur as a manifestation of nervous system drug toxicity or other conditions.

Hyperglycemia - too much glucose in the blood stream
Abnormally increased content of sugar in the blood.

Hypoglycemia - too little glucose in the blood stream
An abnormally diminished concentration of glucose in the blood, which may lead to tremulousness, cold sweat, piloerection, hypothermia, and headache, accompanied by irritability, confusion, hallucinations, bizarre behavior, and ultimately, convulsions and coma.

Idiopathic
Arising spontaneously or from an obscure or unknown cause or the condition may be peculiar to the individual.

Inattention
Difficulty paying attention or failure to pay attention.
  Inattention as a sign of Attention-Deficit Hyperactivity Disorder (ADHD) 
    (a) often fails to give close attention to details or makes careless mistakes in schoolwork, work, or other activities 
    (b) often has difficulty sustaining attention in tasks or play activities 
    (c) often does not seem to listen when spoken to directly 
    (d) often does not follow through on instructions and fails to finish schoolwork, chores, or duties in the workplace ( not due to oppositional behavior or failure to understand instructions) 
    (e) often has difficulty organizing tasks and activities 
    (f) often avoids, dislikes, or is reluctant to engage in tasks that require sustained mental effort ( such as schoolwork or homework) 
    (g) often loses things necessary for tasks or activities (e.g. toys, school assignments, pencils, books, or tools) 
    (h) is often easily distracted by extraneous stimuli 
    (i) is often forgetful in daily activities 
  Inattention, Auditory
Acquired or developmental cognitive disorders of AUDITORY PERCEPTION characterized by a reduced ability to perceive information contained in auditory stimuli despite intact auditory pathways. Affected individuals have difficulty with speech perception, sound localization, and comprehending the meaning of inflections of speech.

Inguinal Hernias
Inguinal hernias are protrusions of soft tissue, such as a portion of the intestine, through a weak spot in a muscle, usually in the abdominal wall. Inguinal hernias occur where the abdomen meets the thigh in the groin region.
Anyone can have an inguinal hernia. Men, women and even children of all ages experience hernias. Hernias are weaknesses or tears in the wall of the abdomen; sometimes they are referred to as ruptures. They typically occur two ways: first, by wear and tear over time (acquired hernias) and secondly from a weakness in the abdominal wall that is present at birth (congenital hernias).  Although many people "live" with hernias for years before they even know it or they become a problem, over time they often get worse due to physical stress or aging. Children's hernias usually are congenital and are present from the time they're born.  Hernias produce different symptoms or feelings. Sometimes you'll notice a protrusion in your groin area between the pubis and the top of the leg or feel pain when you strain during urination or a bowel movement or when you lift a heavy object. The pain can be sharp and immediate. Other times you'll just feel a dull aching sensation, a vague feeling of fullness, nausea or constipation; these feelings typically get worse toward the end of the day or after standing for long periods of time and may disappear when you lie down. And, while persons certainly can live for years with hernias, without treatment they will not disappear.
  If the hernia can be pushed back into the abdominal cavity, it is referred to as a reducible hernia, which while not an immediate health threat, will require surgery to disappear. If it cannot be pushed back, it is nonreducible. This is a condition that may lead to dangerous complications such as the obstruction of the flow of the intestinal contents or intestinal blood supply (strangulation), leading to tissue death. Intestinal obstruction produces nausea, vomiting, loss of appetite, and abdominal pain and usually requires immediate surgery. A strangulated hernia is very painful and requires immediate surgery.
  Over 70% of all hernias occur in the groin area between the pubis and the top of the leg known as the inguinal region of the abdomen, that's why they are called Inguinal Hernias. Here, an abnormal opening occurs in the large sac containing the internal organs, causing some of the organs to protrude. When an abnormal opening or defect occurs on both sides of the groin, it is called a bilateral inguinal hernia. While most hernias are easily treated, in about one in ten people, even after treatment they may return and need to be repaired again. These are called recurrent inguinal hernias. Recurrent hernias are not an indication of your surgeon's ability, but indicate poor tissue healing or trauma to the site of the repair.
  Every year, more than half a million American men, almost one in twenty, will have a hernia that needs surgery. And while the number of women who have problematic inguinal hernias is much less, they are on the rise. Typically men are about 10 times more likely to get an inguinal hernia than women.
  Hernias are caused by congenital (defects at birth) or age-related weaknesses in the abdominal walls. In males, they are caused by an improper closure of the abdominal cavity during the body's development in the womb. They can also be caused by an increase in pressure within the abdominal cavity due to heavy lifting, straining, violent coughing, obesity or pregnancy.

Kyphosis
Abnormal backward (hunched back) curvature of the spine. Abnormally increased convexity in the curvature (backward curve) of the thoracic spine as viewed from the side.

Learning Disability
Conditions characterized by a significant discrepancy between an individual's perceived level of intellect and their ability to acquire new language and other cognitive skills. These disorders may result from organic or psychological conditions. Relatively common subtypes include Dyslexis, dyscalculia, and dysgraphia.

Lordosis
The anterior concavity in the curvature of the lumbar and cervical spine as viewed from the side. The term usually refers to abnormally increased curvature (hollow back, saddle back, swayback) of the lumbar and cervical spine. 

Leukaemia
Leukaemia refers to any of several types of cancers that affect blood cells, including oxygen-carrying red cells; certain infection-fighting white cells, such as granulocytes, macrophages and lymphocytes; and platelets, which aid in blood clotting. 
  According to the American Cancer Society , leukaemia is the sixth leading cause of cancer deaths among men and the seventh leading cause of cancer deaths among women. It accounts for about one-third of all cancer deaths in children. Over 28,500 new cases of leukaemia are diagnosed in the United States each year. Blood cells are made in the bone marrow, the spongy tissue in the centre of bones. A leukaemia begins when an immature blood cell in the marrow, known as a progenitor cell, becomes cancerous, dividing uncontrollably and overriding the body's normal restrictions on cell division. Over time, the marrow becomes crowded with cancerous cells, all of them descendants of the first abnormal cell. The malignant cells may also accumulate in a patient's lymph nodes, spleen, and elsewhere. At the time of diagnosis, up to a trillion leukaemic cells may be present in the body. The mass of leukaemic cells in the marrow suppresses the production of healthy blood cells, giving rise to the symptoms typical of leukaemia. Hence the term itself, which is Greek for white blood ( leukos , "white"; haima , "blood") was applied to the disease. 
  The causes of most types of leukaemia are unknown but 4 known causes of certain types of leukaemia have been identified. These are: 
    Intensive radiation exposure or moderately intense exposure for long periods. 
    Exposure to certain chemicals can also cause leukaemia. Workers exposed to benzene over long periods have an increased risk of developing acute myelocytic leukaemia. Chemotherapy drugs used to treat breast cancer, ovarian cancer, lymphomas, and certain other cancers also increase a patient's risk of later developing acute myelocytic leukaemia. 
    Two viruses , human T-cell leukaemia viruses (HTLV) I and II, are known to cause T-cell leukaemia, a very rare form of lymphocytic leukaemia, in humans. However, only a small percentage of people who are infected with these viruses develop cancer. Although virus-related leukaemia is rare in humans, it is quite common in other animal species, such as cats, chickens, and mice. 
    Genetic factors may also contribute to the development of leukaemia. Some inherited conditions, such as Down syndrome, increase a person's risk of developing leukaemia. 
  Symptoms and Signs. Pale skin, fatigue, and shortness of breath are signs of anaemia . Nose bleeds, gum bleeding, a tendency to bruise easily, and pinhead-sized red spots on the skin reflect the decrease in the concentration of platelets in the blood. A lack of functional white cells makes patients with leukaemia prone to infection. 
  Diagnosis and Treatment.  Bone marrow biopsy and blood tests that monitor blood cell (generally heightened white blood cell and lowered red blood cell counts) are the primary techniques used to diagnose leukaemia. Tests such as chest X rays and examination of the spinal fluid for leukaemic cells can help doctors determine how far the disease has spread. Treatment of leukaemia depends on the type and extent of the disease and is tailored to each individual patient. The main types of treatment in use are: 
    Chemotherapy is the most common treatment used. Antibiotics and transfusions of red cells and platelets help sustain patients whose blood counts are dangerously low because they are receiving intensive chemotherapy. 
    Radiation may also be used to shrink collections of leukaemic cells that accumulate in various parts of the body, such as on the lining of the brain and spinal cord in acute lymphocytic leukaemia, or within lymph nodes in chronic lymphocytic leukaemia. 
    Stem cell transplantation may also be performed if it is thought that chemotherapy alone is not enough or if the patient suffers a relapse. In this procedure, very intensive total body radiation or very high doses of chemotherapy or both are used. The chemotherapy and radiation are designed to destroy all the leukaemic cells in a patient's body; however, this treatment also destroys the blood-forming system in the patient's bone marrow. For this reason, healthy stem cells, the cells in bone marrow that enable long-term formation of blood, must then be infused into a patient to replenish the blood-forming system. The stem cells must come from an immunologically matched donor, usually a sibling or other close relative. 
    Immunotherapy , though still in the experimental stages, is a promising new approach to treating leukaemia. In this technique, highly specific molecules known as monoclonal antibodies are manufactured in the laboratory to target molecules on the surface of leukaemic cells. The antibodies are attached to a radioactive substance, then injected intravenously into a patient. This method provides a convenient means of delivering the radioactive substance directly to leukaemic cells, where it may kill these cells with minimal effect on healthy cells. 

Lupus
Any of several diseases characterized by skin lesions.  A form of cutaneous tuberculosis. It is seen predominantly in women and typically involves the nasal, buccal, and conjunctival mucosa.

Lumbar Spinal Cord Injuries
Spinal cord injury of, relating to, or constituting the spine or the vertebrae between the thoracic vertebrae and sacrum.

Lymphoma
Lymphoma is divided into Hodgkin's disease (or Hodgkin's lymphoma ) and non-Hodgkin's disease . 
  Non-Hodgkin's disease , is really a group of related cancers involving the lymphatic system . There are three major types of childhood non-Hodgkin's lymphomas: lymphoblastic lymphoma , small noncleaved cell lymphoma (either Burkitt's lymphoma or non-Burkitt's lymphoma ), and large cell lymphoma . The type is determined mainly by what the cancer cells look like under a microscope. The way the cells look under a microscope is called the "histology" of the cancer. If a child had lymphoma, it is generally of this type. 
  Hodgkin's disease , or Hodgkin's lymphoma, is a less severe lymphoma. Although the symptoms are similar to those of other lymphomas, the histology of the cancer cells in Hodgkin's disease are different. Hodgkin's disease is easier to treat than other types of lymphomas and is rare in children under 5 years of age. 
  Symptoms and signs. The most common symptom of lymphoma is a painless swelling in the lymph nodes in the neck, underarm, or groin. Other symptoms include fevers, night sweats, tiredness, weight loss, itching, and reddened patches on the skin. Sometimes there is nausea, vomiting, or abdominal pain. Lymphoma risk increases with decreasing immune function, such as that caused by acquired immune deficiency syndrome (AIDS) or exposure to certain infectious agents. Organ transplant recipients are also at higher risk because they take drugs that weaken the immune system as part of the transplantation process. 
  Diagnosis And Treatment.  The doctor will examine the child for swelling or lumps in the neck, underarms, groin, and abdomen. A chest x-ray will usually be done to check for swellings in the chest. If the lymph nodes don't feel normal, or a lump is found in the chest or abdomen, your child's doctor may need to perform a biopsy and look at it under the microscope to see if there are any cancer cells. Prognosis and treatment will depend on the type of lymphoma, the child's age and overall condition and the stage of the cancer. Non-Hodgkin's lymphoma can be cured. Treatment usually consists of chemotherapy, radiation therapy in special situations and bone marrow transplantation is being tested in clinical trials for certain patients. 

Major Depressive Disorder (Unipolar Depression) / Dysthymic Disorder (Chronic, Mild Depression) / Bipolar Disorder (Manic-Depression)
Depressive disorders, which include major depressive disorder (unipolar depression), dysthymic disorder (chronic, mild depression), and bipolar disorder (manic-depression), can have far reaching effects on the functioning and adjustment of young people. Among both children and adolescents, depressive disorders produce an increased risk for illness and interpersonal and psychosocial difficulties, that persist long after the depressive episode is resolved; in adolescents there is also an increased risk for substance abuse and suicidal behaviour. 
A number of studies have reported that up to 2.5% of children and up to 8.3% of adolescents in the U.S. suffer from depression. In addition, research indicates that depression onset is occurring earlier in life today than in past decades. Depression in young people often co-occurs with other mental disorders, most commonly anxiety , disruptive behaviour, or substance abuse disorders, and with physical illnesses, such as diabetes. 
In childhood, boys and girls appear to be at equal risk for depressive disorders; but during adolescence, girls are twice as likely as boys to develop depression.

Marfan Syndrome
A hereditary disorder of connective tissue characterized by tall stature, elongated extremities, subluxation of the lens, dilatation of the ascending aorta, and "pigeon breast." It is inherited as an autosomal dominant trait. 
  Marfan syndrome is a heritable condition caused by a defect in the gene that determines the structure of fibrillin , a protein that is an important part of connective tissue . The primary purpose of connective tissue is to hold the body together and provide a framework for growth and development. In Marfan syndrome, the connective tissue is defective and does not act as it should. Because connective tissue is found throughout the body, Marfan syndrome can affect many body systems, including the skeleton, eyes, heart and blood vessels, nervous system, skin, and lungs. Marfan syndrome affects men, women, and children, and has been found among people of all races and ethnic backgrounds. It is estimated that at least 25,000 people in the United States have the disease. 
  Marfan syndrome affects different people in different ways. Some people have only mild symptoms, while others are more severely affected. In most cases, the disease progresses as the person ages. The body systems most often affected by Marfan syndrome are: 
    Skeleton. People with Marfan syndrome are typically very tall, slender, and loose jointed and often have a long, narrow face, also, the roof of the mouth may be arched, causing the teeth to be crowded. Their arms, legs, fingers, and toes may be disproportionately long in relation to the rest of their body. Other skeletal abnormalities include a sternum (breastbone) that is either protruding or indented, curvature of the spine ( scoliosis ), and flat feet . 
    Eyes . More than half of all people with Marfan syndrome experience some dislocation of one or both lenses of the eye. Many people with Marfan syndrome are also nearsighted ( myopic ), and some can develop early glaucoma (high pressure within the eye) or cataracts (the eye’s lens loses its clearness). 
    Heart and blood vessels (cardiovascular system. Most people with Marfan syndrome have abnormalities associated with the heart and blood vessels. These may include: an abnormal valve motion when the heart beats; leaking of the valve, creating a “heart murmur”; the wall of the aorta (the large artery that carries blood from the heart to the rest of the body) may be weakened and stretch, ( aortic dilation ). Aortic dilation increases the risk that the aorta will tear ( aortic dissection ) or rupture, causing serious heart problems or sometimes even sudden death. 
    Nervous system . The brain and spinal cord are surrounded by fluid contained by a membrane called the dura, which is composed of connective tissue. As people with Marfan syndrome get older, the dura often weakens and stretches, then begins to weigh on the vertebrae in the lower spine and wear away the bone surrounding the spinal cord. These changes may cause only mild discomfort or may lead to radiated pain in the abdomen or legs. This is called dural ectasia . 
    Skin . Many people with Marfan syndrome develop stretch marks on their skin, even without any weight change. These stretch marks can occur at any age and pose no health risk. However, people with Marfan syndrome are also at increased risk for developing an abdominal hernia : a weak part in the abdominal wall that can bulge and contain part of the intestines. 
    Lungs . If the tiny air sacs within the lungs become stretched or swollen, the risk of lung collapse may increase. Rarely, people with Marfan syndrome may have sleep-related breathing disorders such as snoring or sleep apnea . 
  Diagnosis and Treatment. There is no specific test to diagnose Marfan syndrome. The doctor may diagnose Marfan syndrome if the patient has a family history of the disease and specific problems in at least two of the body systems known to be affected. For a patient with no family history of the disease, at least three body systems must be affected before a diagnosis is made. In some cases, a genetic analysis may be useful.  There is no cure for Marfan syndrome. However, a range of treatment options can reduce symptoms. The specific treatment used depends on the system affected: 
  Skeletal . Annual evaluations are important to detect any changes in the spine or sternum. This is particularly important in times of rapid growth, such as adolescence . In some cases, an orthopaedic brace or surgery may be recommended to limit damage and disfigurement. 
    Eyes . Early, regular eye examinations are key to catching and correcting any vision problems associated with Marfan syndrome. In most cases, eyeglasses or contact lenses can correct the problem, although surgery may be necessary in some cases. 
    Heart and blood vessels . Regular check-ups and echocardiograms help the doctor evaluate the size of the aorta and the way the heart is working. The earlier a potential problem is identified and treated, the lower the risk of life-threatening complications. Some heart valve problems can be managed with drugs such as beta-blockers, which may help decrease stress on the aorta. In other cases, surgery to replace a valve or repair the aorta may be necessary. Surgery should be performed before the aorta reaches a size that puts it at high risk for tear or rupture. 
    Nervous system . Although there is no way to prevent dural ectasia from developing, medication may help minimise any associated pain. 
    Lungs . It is especially important that people with Marfan syndrome not smoke, as they are already at increased risk for lung damage. Any problems with breathing during sleep should be assessed by a doctor. 
  While Marfan syndrome is a lifelong disorder, the outlook has improved in recent years. Early diagnosis and advances in medical technology have improved the quality of life for people with Marfan syndrome and lengthened their lifespan. In addition, early identification of risk factors (such as aortic dilation) allows doctors to intervene and prevent or delay complications. 

Meningitis
Inflammation of the coverings of the brain and/or spinal cord. Infections (viral, bacterial, and fungal) are the most common causes of this condition, but hemorrhages, chemical irritation (chemical MENINGITIS), tumors (e.g., carcinomatous meningitis), and other inflammatory conditions may produce this syndrome.

Mental Retardation
Subaverage intellectual ability that is equivalent to or less than an IQ of 70, is present from birth or infancy, and is manifested especially by abnormal development, by learning difficulties, and by problems in social adjustment.  Subnormal intellectual functioning which originates during the developmental period. This has multiple potential etiologies, including genetic defects and perinatal insults. Intelligence quotient (IQ) scores are commonly used to determine whether an individual is mentally retarded. IQ scores between 70 and 79 are in the borderline mentally retarded range. Scores below 67 are in the retarded range.
  Level I mental retardation - mild - generally IQ is between 50 and 70
  Level II mental retardation - moderate - generally IQ is between 30 and 50
  Level III mental retardation - severe - generally IQ is from 20 to 30
  Level IV mental retardation - profound - generally IQ is below 20

Menstruation
The normal physiologic discharge through the vagina of blood and mucosal tissues from the nonpregnant uterus. Variations of menstruation which may be indicative of disease include: Hypomenorrhea, Polymenorrhea, Oligomenorrhea, Menorrhagia, etc.
Amenorrhea - Absence of menstruation.
Dysmenorrhea - Painful menstruation.
Menorrhagia - Excessive menstrual flow.
Metrorrhagia - Uterine bleeding, usually irregular or acyclic, between periods.
Oligomenorrhea - Abnormally infrequent menstruation.

Mononucleosis, Infectious
An acute infectious disease associated with Epstein-Barr virus and characterized by fever, swelling of lymph nodes, and lymphocytosis (excess of normal lymphocytes). An abnormal increase of lymphocytes (white blood cells) in the blood; specifically : INFECTIOUS MONONUCLEOSIS . A common, acute infection usually caused by the Epstein-Barr virus (HERPESVIRUS 4, HUMAN). There is an increase in mononuclear white blood cells and other atypical lymphocytes, generalized lymphadenopathy, splenomegaly, and occasionally hepatomegaly with hepatitis. Symptoms include extreme fatigue and malaise.

Movement Disorders
Syndromes which feature DYSKINESIAS as a cardinal manifestation of the disease process. Included in this category are degenerative, hereditary, post-infectious, medication-induced, post-inflammatory, and post-traumatic conditions.

Multiple Sclerosis
Progressive, chronic degenerative disease of the myelin sheath covering nerves - the cause is unknown and the disease can be terminal - generally appears between ages 20 and 40
  A demyelinating disease marked by patches of hardened tissue in the brain or the spinal cord and associated especially with partial or complete paralysis and jerking muscle tremor. An autoimmune disorder mainly affecting young adults and characterized by destruction of myelin in the central nervous system. Pathologic findings include multiple sharply demarcated areas of demyelination throughout the white matter of the central nervous system. Clinical manifestations include visual loss, extra-ocular movement disorders, paresthesias, loss of sensation, weakness, dysarthria, spasticity, ataxia, and bladder dysfunction. The usual pattern is one of recurrent attacks followed by partial recovery (see MULTIPLE SCLEROSIS, RELAPSING-REMITTING), but acute fulminating (coming on suddenly with great severity) and chronic progressive forms are also possible.

Muscular Dystrophy
A general term for a group of inherited disorders which are characterized by progressive degeneration of skeletal muscles. Any of a group of hereditary diseases characterized by progressive wasting of muscles.
  Facioscapulohumeral Muscular Dystrophy
A wasting away of the muscles of the upper body, particularly of the face, arm and shoulder region. An autosomal dominant degenerative muscle disease characterized by slowly progressive weakness of the muscles of the face, upper-arm, and shoulder girdle. The onset of symptoms usually occurs in the first or second decade of life. Affected individuals usually present with impairment of upper extremity elevation. This tends to be followed by facial weakness, primarily involving the orbicularis oris and orbicuaris oculi muscles.
  Duchenne Muscular Dystrophy / pseudohypertrophic (false hypertrophy)
Muscles atrophy and waste away but their outward appearance is normal or hypertrophied. An X-linked recessive muscle disease caused by an inability to synthesize DYSTROPHIN, which is involved with maintaining the integrity of the sarcolemma. Muscle fibers undergo a process that features degeneration and regeneration. Clinical manifestations include proximal weakness in the first few years of life, pseudohypertrophy, cardiomyopathy (see MYOCARDIAL DISEASES), and an increased incidence of impaired mentation. Becker muscular dystrophy is a closely related condition featuring a later onset of disease (usually adolescence) and a slowly progressive course.

Myasthenia Gravis
Myasthenia gravis is an autoimmune disease affecting the neuromuscular junction and producing weakness of voluntary muscles. It is a chronic disease deriving its name from Latin and Greek words meaning "grave muscle weakness." 

Obsessive-Compulsive Disorder ( OCD)
Characterised by intrusive, unwanted, repetitive thoughts and rituals performed out of a feeling of urgent need; at least one-third of adult cases begins in childhood. 

Osgood-Schlatter Condition / Osgood-Schlatter Disease
Prevalent in adolescents, the quadriceps tend to pull the tibial tuberosity away from the rest of the bone causing pain of varying degrees.
  Osgood-Schlatter disease is one of the most common causes of knee pain in active adolescents. It is a generally benign disturbance at the junction of the patellar tendon and the tibial tubercle apophysis, and treatment during its 12- to 24-month course should be matched to severity. Mild symptoms require only patient education and moderation of activity, but severe symptoms call for a period of rest (or, rarely, immobilization) followed by aggressive quadriceps strengthening. Other conditions such as Sinding-Larsen-Johansson disease may occur simultaneously, and long-term effects can include a prominence on the anterior knee or painful kneeling. Osgood-Schlatter disease (OSD), a very common cause of knee pain in adolescents, is a disturbance of the patellar tendon attachment to the tibial tubercle apophysis. The condition most commonly affects young people who participate in jumping and cutting sports, such as basketball, volleyball, figure skating, gymnastics, and soccer, and is bilateral in about 20% of cases. The exact cause is unknown, but it probably involves repetitive microavulsion (overuse) of the chondrofibroosseous tibial tubercle. OSD typically develops in girls between the ages of 8 and 13 and in boys between 10 and 15--at the beginning of their growth spurt. The condition has been more frequent in boys, although the ratio may be equalizing with girls' increased participation in sports. Typically, OSD is self-limiting, but it can take 12 to 24 months to run its course. Pain usually remits on skeletal maturity, but a small percentage of patients develop a painful ossicle, which can necessitate surgical excision. On long-term follow-up, 24% of patients have some limitation of activities, and 60% have discomfort with kneeling. 

Osteoarthritis
A progressive, degenerative joint disease, the most common form of arthritis, especially in older persons. The disease is thought to result not from the aging process but from biochemical changes and biomechanical stresses affecting articular cartilage. 

Osteochondritis / Osteochondrosis
Degeneration followed by reossification of one or more ossification centers in children.
Osteochondritis dissecans - The term 'dissecans' comes from 'dis' meaning 'from' and 'secare' meaning 'cut off,' and is not to be confused with 'desiccans' derived from 'desiccare' meaning to 'dry up.' Dissecans refers to the appearance of part of the bone having been cut away. There are a large number of possible localizations of osteochondritis dissecans.
  Thiemann Epiphyseal Disease (phalangeal epiphyses)
  Freiberg infraction (of the head of the second metatarsal) 
  Panner (of the capitellum of the humerus)
  Kienbock (semilunar bone of the wrist)
  Larsen-Johanssen (of the patella)
  Legg-Calve-Perthes disease (femoral epiphysis - head of femur) 
  Osgood-Schlatter disease (tibial tuberosity) 
  Kohler disease (foot's tarsal navicular) 
  Scheuermann disease (spinal vertebral ring epiphyses) 
  Sever disease (apophysis of os calcis - wrist) 

Osteochondrodysplasias are a group of hereditary disorders in which bone or cartilage grows abnormally, so that the skeleton develops abnormally. Many types of osteochondrodysplasia cause dwarfism. Achondroplasia is the most common of the many types of short-limbed dwarfism. 

Osteogenesis Imperfecta (brittle bone disease)
A condition generally associated with brittle, easily broken bones - in many cases is thought to be the result of mutation rather than heredity
  Autosomal dominant COLLAGEN DISEASES resulting from defective biosynthesis of COLLAGEN TYPE I and characterized by brittle, osteoporotic, and easily fractured bones. It may also present with blue sclerae, loose joints, and imperfect dentin formation. There are four major types, I-IV.  AKA - brittle bone disease

Osteomyelitis
Osteomyelitis is a bone infection that is often caused by a bacterial staphy infection, though other types of bacteria can cause it, too. In kids and teens, osteomyelitis usually affects the long bones of the arms and legs.  It is marked by local death and separation of tissue.  Bacteria can infect bones in a couple of ways. One way is by direct infection, when bacteria enter the body's tissues through a wound and travel to the bone - which is what happens when someone steps on a nail. Bacteria that normally live in our sweaty sneakers can be driven through the puncture wound caused by the nail, deep into the bottom of the foot. Once in the deep tissues of the foot, bacteria can easily spread to bone.  Bacteria also can travel into the bone through the bloodstream from other infected areas in the body.  It is more common in guys than girls. People with osteomyelitis often feel severe pain in the infected bone. They may have fever and chills, feel tired or nauseated, or have a general feeling of not being well. The skin above the infected bone may be sore, too.  If the osteomyelitis developed after an open wound, the injured area may begin to hurt again after initially seeming to get better. Often, the doctor will take a bone X-ray, which may show whether an infection in the bone is present. However, X-rays are often negative if someone has only had osteomyelitis for a short while. If the doctor strongly suspects osteomyelitis, he or she may suggest a bone scan that provides a more detailed look at the bone.  Treatment of osteomyelitis depends on the severity of the infection and whether it is acute (recent) or chronic (has been present for a longer period of time). The doctor may use a needle to remove a bacteria sample from the bone to help identify the bacteria responsible for the infection. This is called needle aspiration. The doctor will then be able to choose the correct antibiotic to treat that particular infection. In some cases, the osteomyelitis will become severe and a cavity or hole will develop in the bone. Pus - a large collection of bacteria and white blood cells - may have formed in this cavity. If this has happened, the doctor may perform a surgical procedure to help drain the pus out of the bone so the bone can heal properly. Osteomyelitis can be difficult to treat. Chronic osteomyelitis is often more difficult to treat and is more likely to return, even after treatment. After being diagnosed with osteomyelitis, the patient may be admitted to the hospital for a short stay, so that intravenous antibiotics can be given (directly into a vein) to fight the infection. Once the condition improves the patient may continue to need oral antibiotics for several more weeks. Chronic osteomyelitis may continue to return, not going away completely. In this case, doctors will sometimes need to perform surgery, in which they debride (thoroughly clean out) the infected area. This means that during the operation, they open up the area and clean out pus and infected matter and scrape away any dead or diseased tissue, so healing can begin.  Most people recover completely from osteomyelitis.

Osteopetrosis
Osteopetrosis is part of a spectrum of diseases characterised by generalised increase in skeletal density. Several forms of osteopetrosis have been described with overlapping clinical and radiographic features. Two of the main forms of osteopetrosis are the following: 
  1. Early-onset or precocious form of osteopetrosis is most frequently discovered during the first months of life; it may appear as failure to thrive, malignant hypocalcemia , anaemia with thrombocytopenia, or severe, perhaps overwhelming infection. It generally follows a progressive course leading to death at an early age.  Inheritance is generally autosomal recessive. Rarely, fractures lead to medical attention. Hyperostosis may crowd the marrow cavity, with anaemia and extramedullary hematopoiesis, hepatosplenomegaly, and thrombocytopenia. Anaemia appears to result not from inadequate erythropoiesis but from excessive hemolysis. A defect in macrophage killing of bacteria may account for recurrent infection. Bony encroachment on the optic foramina may lead to optic atrophy and blindness. Hypocalcemia is not uncommon, and serum phosphorus may be low. Serum alkaline phosphatase activity is elevated. Radiographically, the diagnostic findings are a generalised increase in bone density, with defective metaphyseal modelling, and a "bone in bone" appearance most marked in vertebral bodies. Irregular condensation of bone at the metaphyses may produce the appearance of parallel plates of dense bone at the ends of the long bones. Treatment is aimed at decreasing or arresting progressive hyperostosis, correcting anaemia and thrombocytopenia, and treating infections. A regimen of oral cellulose phosphate, prednisone, and low calcium diet has been reported to be effective in some but not all patients. The prednisone arrests the progression of anaemia Bone marrow transplantation has been reported to be curative in several patients. Generally, the prognosis for survival is poor, and death in the first few months or year from anaemia, bleeding, or overwhelming infection is not uncommon. 
  2. Osteopetrosis tarda is usually a milder disorder with delayed manifestations and often referred to as Albers-Schonberg disease . This form of osteopetrosis is found in childhood, adolescence, or young adult life because of fractures (about 10% of patients), mild craniofacial disproportion, mild anaemia, complications arising from neurological involvement, or osteitis with osteonecrosis (usually of the mandible). Increased bone density may be discovered incidentally on x- rays. 
Most cases appear to represent autosomal dominant inheritance.  Skeletal x- rays show generalised increase in density of cortical bone, with a club-shaped appearance of the long bones due to defective metaphyseal modelling. Over 50% of patients have longitudinal or transverse dense striations at the ends of the long bones. The vertebrae show alternating lucent and dense bands.  Management should be directed at recognition and treatment of complications, with frequent testing of visual fields and acuity and periodic x- rays of the optic foramina. Transfusion and splenectomy may be useful in some patients. 

Osteoporosis
A condition that affects especially older women and is characterized by decrease in bone mass with decreased density and enlargement of bone spaces producing porosity and fragility.  Reduction of bone mass without alteration in the composition of bone, leading to fractures. Primary osteoporosis can be of two major types: postmenopausal osteoporosis and age-related or senile osteoporosis.

Paralysis
A general term most often used to describe severe or complete loss of muscle strength due to motor system disease from the level of the cerebral cortex to the muscle fiber. This term may also occasionally refer to a loss of sensory function. 

Paraplegia
Severe or complete loss of motor function in the lower extremities and lower portions of the trunk. This condition is most often associated with SPINAL CORD DISEASES, although BRAIN DISEASES; PERIPHERAL NERVOUS SYSTEM DISEASES; NEUROMUSCULAR DISEASES; and MUSCULAR DISEASES may also cause bilateral leg weakness.

Paresis
A general term referring to a mild to moderate degree of muscular weakness, occasionally used as a synonym for PARALYSIS (severe or complete loss of motor function). Bilateral lower extremity paresis is referred to as PARAPARESIS.

Paranoid
Characterized by suspiciousness, persecutory trends, or megalomania - extremely fearful.

Pes Planus (flat feet)
A condition in which one or more of the arches of the foot have flattened out. AKA - flat feet

Pigeon Toes
Also referred to as intoeing. Here the child's toes point inward when walking or, sometimes, even at rest. Intoeing can be caused by many different types of leg and foot problems, including abnormal rotation of the leg bones (either internal tibial torsion or femoral anteversion) or an abnormal curvature of the foot ( metatarsus adductus ). 

Petit Mal Seizure / Epilepsy
Brief and general seizure with a 10 to 30 second loss of consciousness eye or muscle fluttering and a sometimes loss of muscle tone - it may be so brief that neither the person or observers are aware of the seizure
  A childhood seizure disorder characterized by rhythmic electrical brain discharges of geneneralized onset. Clinical features include a sudden cessation of ongoing activity usually without loss of postural tone. Rhythmic blinking of the eyelids or lip smacking frequently accompanies the seizure. The usual duration is 5-10 seconds, and multiple episodes may occur daily. Juvenile absence epilepsy is characterized by the juvenile onset of absence seizures and an increased incidence of myoclonus and tonic-clonic seizures.

Phenylketonuria / PKU
A hereditary disease caused by the body's failure to oxidize an amino acid - if not treated by a proper diet within the first three years of life, permanent brain damage will result - however, if immediately found after birth and treated with proper diet, a normal life is possible - for this reason every child born is given a test for this birth defect.
  An inherited human metabolic disease that is characterized by inability to oxidize a metabolic product of phenylalanine and by severe mental deficiency -- abbreviation PKU.
  A group of autosomal recessive disorders marked by a deficiency of the hepatic enzyme PHENYLALANINE HYDROXYLASE or less frequently by reduced activity of DIHYDROPTERIDINE REDUCTASE (i.e., atypical phenylketonuria). Classical phenylketonuria is caused by a severe deficiency of phenylalanine hydroxylase and presents in infancy with developmental delay; SEIZURES; skin HYPOPIGMENTATION; ECZEMA; and demyelination in the central nervous system. Easily diagnosed and treated through diet.

Phobia
Anxiety disorders in which the essential feature is persistent and irrational fear of a specific object, activity, or situation that the individual feels compelled to avoid. The individual recognizes the fear as excessive or unreasonable. An exaggerated usually inexplicable and illogical fear of a particular object, class of objects, or situation.

Poliomyelitis
An acute infectious disease of humans, particularly children, caused by any of three serotypes of human poliovirus (POLIOVIRUS). Usually the infection is limited to the gastrointestinal tract and nasopharynx, and is often asymptomatic. The central nervous system, primarily the spinal cord, may be affected, leading to rapidly progressive paralysis, coarse FASCICULATION and hyporeflexia. Motor neurons are primarily affected. Encephalitis may also occur. The virus replicates in the nervous system, and may cause significant neuronal loss, most notably in the spinal cord.

Pre-menstrual Sndrome (PMS)
Pre-menstrual syndrome (PMS) is characterised by a combination of physical and psychological symptoms that occur in a cyclic pattern, appearing during the week before the menstrual period and often improving with the onset of bleeding. Research suggests that as many as 75% of menstruating women have some pre-menstrual syndrome symptoms. A much smaller number, (probably 3 -8 % of women) have a more severe syndrome which can be disabling. 
Symptoms and Signs. The symptoms of PMS can be extremely distressing and usually include: 
    Irritability 
    Anxiety or depression 
    Diminished self-esteem 
    Difficulty concentrating 
    Sleep problems 
    Appetite changes 
    Low energy 
    Bloating, headache and breast swelling and tenderness. 
Diagnosis and Treatment. The types and severity of symptoms vary from one woman to another. Some have defined the term PMS as requiring that at least 1 psychological and 1 physical symptom be present monthly during the pre-menstrual period. Women may want to seek treatment when their symptoms are so severe that they seriously interfere with their daily activities. Many treatments have been tried for alleviating the symptoms of PMS but no treatment has been found that is consistently effective. Treatments include: 
    Lifestyle and stress management. 
    Dietary restrictions (salt or carbohydrate). 
    Diuretics. 
    Prostaglandin inhibitors. 
    Progesterone treatment. 
    Ovulation inhibitors. 
    Vitamins. 
    Lithium and antidepressants. There is some evidence to suggest that a brain chemical, serotonin, may play a role in severe forms of PMS. Antidepressants that alter the serotonin system have been shown to help many women with severe forms of PMS who failed other treatments. These have become the first line treatments at this time due to their low incidence of side effects and their good success rate. 

Quadriplegia
Severe or complete loss of motor function in all four limbs which may result from BRAIN DISEASES; SPINAL CORD DISEASES; PERIPHERAL NERVOUS SYSTEM DISEASES; NEUROMUSCULAR DISEASES; or rarely MUSCULAR DISEASES. 

Rheumatic Fever
A disease of unknown origin that often affects children and adolescents following a streptococcal infection, such as strep throat - it is frequently followed by heart or kidney disease.
  A febrile (fever) disease occurring as a delayed result of streptococci infections and characterized by multiple focal inflammatory lesions of the connective tissue structures, especially of the heart, blood vessels, and joints (polyarthritis), and by the presence of Aschoff bodies in the myocardium and skin.
  Aschoff Bodies - A small round or oval, mostly subcutaneous nodule made up chiefly of a mass of Aschoff bodies and seen in cases of rheumatic fever. It is differentiated from the RHEUMATOID NODULE which appears in rheumatoid arthritis, most frequently over bony prominences. 

Rheumatic Heart Disease
A condition which often follows or is caused by rheumatic fever - it is associated with damage to the heart and the valves of the heart.  The most important manifestation of and sequel to rheumatic fever, i.e., any cardiac involvement in rheumatic fever. 

Reye's Syndrome
Associated with viral infections such as the flu - should not give aspirin to children or adolescents with chicken pox, flu, or other viral infections because it may induce this syndrome
  Reye's Syndrome, a deadly disease, strikes swiftly and can attack any child or adult without warning.  All body organs are affected, with the liver and brain suffering most  seriously.  While the cause and cure remain unknown, research has established a link between Reye's Syndrome and the use of aspirin and other salicylate-containing medications.
  Reye's Syndrome is a disease which affects all organs of the body, but most lethally the liver and the brain. Reye's Syndrome is a two-phase illness because it is almost always associated with a previous viral infection, such as influenza, cold, or chicken pox. Scientists do know that Reye's Syndrome is not contagious and the cause is unknown. Reye's Syndrome is often misdiagnosed as encephalitis, meningitis, diabetes, drug overdose, poisoning, Sudden Infant Death Syndrome, or psychiatric illness. 
  Reye's Syndrome tends to appear with greatest frequency during January, February, and March when influenza is most common. Cases are reported in every month of the year. An epidemic of flu or chicken pox is commonly followed by an increase in the number of cases of Reye's Syndrome. When Reye's Syndrome develops, it typically occurs when a person is beginning to recover from a viral illness. Abnormal accumulations of fat begin to develop in the liver and other organs of the body, along with a severe increase of pressure in the brain. Unless diagnosed and treated successfully, death is common, often within a few days. A person's life depends upon early diagnosis. Statistics indicate an excellent chance of recovery when Reye's Syndrome is diagnosed and treated in its earliest stages. The later the diagnosis and treatment, the more severely reduced are chances for successful recovery and survival. 

Rheumatoid Arthritis
A chronic systemic disease, primarily of the joints, marked by inflammatory changes in the synovial membranes and articular structures, widespread fibrinoid degeneration of the collagen fibers in mesenchymal tissues, and by atrophy and rarefaction of bony structures. Etiology is unknown, but autoimmune mechanisms have been implicated.

Rheumatoid Arthritis, Juvenile
Rheumatoid arthritis of children occurring in three major subtypes defined by the symptoms present during the first six months following onset: systemic-onset (Still's Disease, Juvenile-Onset) polyarticular-onset, and pauciarticular-onset. Adult-onset cases of Still's disease (STILL'S DISEASE, ADULT-ONSET) are also known. Only one subtype of juvenile rheumatoid arthritis (polyarticular-onset, rheumatoid factor-positive) clinically resembles adult rheumatoid arthritis and is considered its childhood equivalent.

Schizophrenia
A severe emotional disorder of psychotic depth characteristically marked by a retreat from reality with delusion formation, hallucinations, emotional disharmony, and regressive behavior. - A psychotic disorder characterized by loss of contact with the environment, by noticeable deterioration in the level of functioning in everyday life, and by disintegration of personality expressed as disorder of feeling, thought (as in hallucinations and delusions), and conduct.
  Schizophrenia, Catatonic
A type of schizophrenia characterized by abnormality of motor behavior which may involve particular forms of stupor, rigidity, excitement or inappropriate posture.
  Hebephrenic Schizophrenia
A type of schizophrenia characterized by frequent incoherence; marked loosening of associations, or grossly disorganized behavior and flat or grossly inappropriate affect that does not meet the criteria for the catatonic type; associated features include extreme social withdrawal, grimacing, mannerisms, mirror gazing, inappropriate giggling, and other odd behavior. - A form of schizophrenia characterized especially by incoherence, delusions lacking an underlying theme, and affect that is flat, inappropriate, or silly.
  Paranoid Schizophrenia
Schizophrenia characterized especially by persecutory or grandiose delusions or hallucinations or by delusional jealousy 

Scoliosis
a lateral curve of the spine. - An appreciable lateral deviation in the normally straight vertical line of the spine. 

Sickle Cell Anemia
A heredity chronic disease that primarily affects people of African and Mediterranean populations - it is characterized by crescent-shaped red blood cells which sometimes "clump together" to obstruct capillary blood flow and thereby causes fever and severe pain.  The disease is characterized by chronic hemolytic anemia (anemia due to decreased life span of red blood cells), episodic painful crises, and pathologic involvement of many organs.  
  A sickle is a farm tool with a curved, sharp edge for cutting wheat. Sickle cell anemia is a disease of the blood that gets its name because the blood cells are shaped like a sickle.  Normal red blood cells are soft and round like teeny tiny little doughnuts. These normal cells bend and flow easily through small, tube-like blood vessels to deliver oxygen to all parts of the body. But sickle cells are different. They're much stiffer, with a curved shape.  The hard, curved edges of sickle cells can make these cells get clogged up inside of smaller blood vessels. This keeps blood from flowing properly in the body. Important organs like the brain, heart, or kidneys need constant blood flow to stay healthy. Although the body attacks the sickle cells and destroys them, it can't make new blood cells fast enough to replace the old ones. This can cause the body to have too few red blood cells, a problem known as anemia. Kids who have sickle cell anemia may feel pain in their chest, stomach, or bones when a blood vessel gets clogged with sickle cells. The pain can last a few minutes or several days, and it might hurt a lot or just a little. Nobody knows exactly when sickle cells might get stuck or which blood vessels might get clogged, but doctors and nurses can help by giving strong pain medicine. Because kids with sickle cell anemia don't have enough normal red blood cells, they get tired more easily. They also get infections more often than other kids do, and they are in danger of developing skin ulcers that are hard to heal. They may not grow as fast or feel as hungry as their friends. Sometimes the whites of their eyes have a yellowish color, known as jaundice, and they may have to go to the bathroom a lot. In little kids - usually under age 2 - sickle cell anemia can cause their hands and feet to swell and hurt. 
  Sickle cell anemia is an inherited disease. More African-Americans have sickle cell anemia than any other group of people. About one out of every 500 African-Americans has the disease. But some people whose ancestors came from countries around the Mediterranean Sea - like Greece, Italy, and Saudi Arabia - have sickle cell genes, too. 
Most kids with sickle cell anemia take penicillin (say: peh-nuh-sih-lin), a drug that helps prevent infections. A doctor may also prescribe a vitamin supplement called folic acid. Folic acid helps the body make new red blood cells. 
  Taking penicillin or vitamins does not cure sickle cell anemia, but it can help keep a kid with sickle cell anemia from getting sick. If an infection occurs, a kid who has sickle cell anemia should see a doctor right away to get treatment.  Pain medicine also helps kids with this disease.  Severe attacks of pain or possibly serious infections may mean that kids with sickle cell anemia have to go to the hospital to get intravenous (IV) fluids, antibiotics, or other medications. Sometimes kids with sickle cell anemia need blood transfusions.  A blood transfusion raises the amount of normal hemoglobin in the blood and decreases the chances that blockage will occur in the blood flow. Blood transfusions may be needed if a kid has lots of sickle cell problems, such as lots of blood vessel blockage to the brain or heart, or if a kid tends to have severe anemia.  A bone marrow transplant sometimes can cure sickle cell anemia. Bone marrow transplants replace the sickle cells with healthy cells from a donor. 
If someone has sickle cell anemia, the disease won't go away. But taking penicillin every day helps prevent infections in kids with the disease.  
  It's important for kids with sickle cell anemia to stay as healthy as possible. That means eating healthy foods, getting plenty of rest, and drinking lots of water. Kids with the disease can play games and sports, but they should avoid getting too hot, too cold, or too tired.  When kids with sickle cell disease have a fever or aches, they should tell their parents or teachers right away. A fever is the body's signal that an infection may be on its way, and pain may mean that sickle cells are getting stuck in the blood vessels. 

Spastic
An involuntary and abnormal muscular contraction resulting jerky, uncoordinated movements - A form of muscle hypertonia associated with upper MOTOR NEURON DISEASE. Resistance to passive stretch of a spastic muscle results in minimal initial resistance (a "free interval") followed by an incremental increase in muscle tone. Tone increases in proportion to the velocity of stretch. Spasticity is usually accompanied by HYPERREFLEXIA and variable degrees of MUSCLE WEAKNESS.

Spina Bifida
A congenital separation or non-union of the spinal column.
  Congenital defects of closure of one or more vertebral arches, which may be associated with malformations of the spinal cord, nerve roots, congenital fibrous bands, lipomas, and congenital cysts. These malformations range from mild (e.g., SPINA BIFIDA OCCULTA) to severe, including complete failure of neural tube and spinal cord fusion, resulting in exposure of the spinal cord at the surface. Spinal dysraphism includes all forms of spina bifida. The open form is called SPINA BIFIDA CYSTICA and the closed form is SPINA BIFIDA OCCULTA. 
  When most people talk about spina bifida, though, they're referring to myelomeningocele (say: my-low-meh-nin-go-seal), from words meaning "spine" and "swelling." In this kind, the baby is born with something that looks like a big blister or sac on her back. This sac contains nerves and part of the spinal cord, which pushes through the opening.
  Because the spinal cord hasn't developed properly, a baby with this type of spina bifida will have some paralysis (say: puh-ral-eh-sis), which means she won't be able to move some of her muscles or to feel things on some parts of her body. How much paralysis there is depends on where the opening is on the baby's back. The lower the opening is, the fewer nerves are affected and the less paralysis there is. But the higher the opening is, the more paralysis there is. This is why some kids with spina bifida can walk and some can't.
  Most kids with myelomeningocele also have hydrocephalus. This happens when there's too much fluid around the brain. Most kids with spina bifida also have problems with their bowels and bladder. The nerves that send and receive messages from the brain can't do their job, so it's hard for kids to tell when they need to go to the bathroom.
  No one is really sure why some kids are born with spina bifida, but doctors and scientists have discovered some possible reasons. One thing they've learned about is the importance of folic acid. Folic acid is one of the B vitamins found in foods like broccoli, spinach, egg yolks, and oranges. If a woman doesn't have enough folic acid in her diet, her baby is more likely to have spina bifida.  Another possible cause might be if a woman has a high fever early in her pregnancy. Scientists are also studying the roles that genes, the environment, and certain chemicals and medicines might play in causing spina bifida.

Talipes
Club foot
  Talipes Cavus
Alterations or deviations from normal shape or size which result in a disfigurement of the foot.
  Talipes Equinovarus
A deformed foot in which the foot is plantarflexed, inverted and adducted. (looks almost like a horse hoof)

Tay Sachs Disease
An autosomal recessive inherited, often fatal disease characterized by the onset in the first 6 months of life of an exaggerated startle response, delay in psychomotor development, hypotonia (followed by spasticity), visual loss, and a  cherry red spot on the macula lutea of the retina. Hexosaminidase A (an enzyme hydrolyzing glucosides, galactosides) is deficient, leading to the accumulation of glycosphingolipids in neurons of the central nervous system and retina. This condition is strongly associated with Jewish ancestory.

Thoracic Spinal Cord Injury
Injury of or relating to spine or the spinal vertebral colum between the neck and the abdomen. neck and the spine or the spinal or vertebral column in the neck.  Thoracic spinal cord injury is associated with paraplegia.

Tourette’s Syndrome 
Tourette’s Syndrome (TS) is characterised by repeated, involuntary movements and uncontrollable vocal sounds, known as tics . Affecting approximately 100,000 Americans in its full-blown form, TS generally emerges during childhood or early adolescence. Although the basic cause of TS is unknown, current research suggests there is a genetic abnormality affecting certain neurotransmitters in the brain (particularly dopamine ), and that varying environmental factors, possibly including infections, modifies the clinical expression of the disorder. TS is up to 3 times more common in males. 
  Symptoms and Signs.  The characteristic symptoms of TS are complex tics. These are much more than an involuntary twitch or blink of the eye. Other symptoms and signs include echoalia (repeating what has been said), compulsive swearing and may include self-destructive, aggressive behaviour. TS is often seen in association with some other neurological disorders, particularly OCD . Researchers are investigating the neurological similarities between OCD and TS to determine whether a genetic relationship exists. 
  Diagnosis and Treatment.  Diagnosis of TS is based on the presence of the characteristic symptoms. In most cases, Tourette’s Syndrome is not disabling, symptoms don’t impair patients, development proceeds normally, and there is no need for treatment. However, some effective medications are available in the rare instances when symptoms interfere with functioning (antipsychotic drugs seem to help although psychosis is not the problem). Children with TS can generally function well at home and in the regular classroom. If they have an accompanying learning disability or other disorder, such as ADHD or OCD, they may require tutoring, special classes, psychotherapy, or medication. 

Traumatic Brain Injury
Acute and chronic (see also BRAIN INJURIES, CHRONIC) injuries to the brain, including the cerebral hemispheres, CEREBELLUM, and BRAIN STEM. Clinical manifestations depend on the nature of injury. Diffuse trauma to the brain is frequently associated with DIFFUSE AXONAL INJURY or COMA, POST-TRAUMATIC. Localized injuries may be associated with NEUROBEHAVIORAL MANIFESTATIONS; HEMIPARESIS, or other focal neurologic deficits.