RETT SYNDROME:

Girls with Rett Syndrome appear to develop normally until 6 to 18 months of age. They then enter a period of regression, losing speech and hand skills they had acquired. Most girls develop seizures, repetitive hand movements, irregular breathing and motor-control problems. A slowing of the rate of head growth also
becomes apparent. Most researchers agree that RS is a developmental disorder rather than a progressive, degenerative disorder. The girls can live to adulthood, but most never regain the ability to use their hands or to speak.

CHILDHOOD DISINTEGRATIVE DISORDER:

Childhood Disintegrative Disorder (also known as Heller's Syndrome) is a condition in which a child develops normally for 2 years, then begins to lose ground. Previous gains in language and social skills, motor abilities, play, and even in continence are eroded.  For more information, click here.

 A.    Apparently normal development for at least the first 2 years after birth 
           as manifested by the presence of age- appropriate verbal and nonverbal 
           communication, social relationships, play, and adaptive behavior.

 B.   Clinically significant loss of previously acquired skills (before age 10 years) 
           in at least two of the following areas:

          (1) expressive or receptive language
          (2) social skills or adaptive behavior
          (3) bowel or bladder control
          (4) play
          (5) motor skills

C.   Abnormalities of functioning in at least two of the following areas:

         (1)  Qualitative impairment in social interaction 
              (e.g., impairment in nonverbal behaviors, failure to develop peer 
               relationships, lack of social or emotional reciprocity)
         (2)  qualitative impairments in communication (e.g. delay or lack of spoken 
               language, inability to initiate or sustain a conversation, stereotyped and 
               repetitive use of language, lack of varied make-believe play).
         (3)  restricted, repetitive, and stereotyped patterns of behavior, interests, and 
               activities, including motor stereotypes and mannerisms.

D.    The disturbance is not better accounted for by another specific 
           Pervasive Developmental Disorder or by Schizophrenia.

LANDAU-KLEFFNER SYNDROME:

Landau-Kleffner syndrome (LKS), also called acquired epileptiform aphasia, is a rare, childhood neurological disorder characterized by the sudden or gradual development of aphasia (loss of language) and an abnormal electro-encephalogram (EEG). LKS affects the parts of the brain that control speech and comprehension. The disorder usually occurs in children between the ages of 3 and 7. Typically, these children develop normally and then, for no apparent reason, they lose the ability to understand others and to speak. While many of the affected individuals have seizures, some do not. The disorder is difficult to diagnose and may be misdiagnosed as autism, pervasive developmental disorder, hearing impairment, learning disability, auditory/verbal processing disorder, attention deficit disorder, mental retardation, childhood schizophrenia, or emotional/behavioral problems. For more links, click here.

All children with LKS have abnormal electrical activity in one, sometimes both temporal lobes, the area of the brain responsible among other functions for processing language. This epileptiform activity shows up in an EEG test particularly when the child is asleep.

About two-thirds of LKS children have seizures. Seizures during the night are common. Many children have very few seizures and these are readily controlled by anti-epileptic drugs. Some children never have obvious seizures: it is not necessary to have a seizure to have LKS. A few children have many seizures which are harder to control.

The language disorder in most children affects comprehension or understanding. Many LKS children become unable to understand their own name. They are also likely to have difficulty recognizing environmental sounds such as the telephone ringing. These children may appear to be deaf.

Expressive language - the ability to speak is often seriously affected; some children lose their speech completely. Rarely, a child may be able to understand language, but have difficulty with speaking.

Behavioural problems are common, especially hyper-activity, poor attention, depression and irritability.

Some children have episodes of very abnormal "autistic type behaviour" with symptoms such as avoidance of contact with family and friends (avoidance of eye contact is common) extreme pickiness over food, very disturbed sleep, attacks of rage and aggression, insensitivity to pain, bizarre and inappropriate and repetitive play.

There may be temporary other neurological problems such as loss of bladder and bowel control, episodes of visual disturbances may occur, the child can see but does not understand what he sees. He may have difficulty recognizing family and friends or common objects, such as food and clothes.

23: July 24, 2002