Rett syndrome

Rett syndrome is a pervasive developmental disorder due to encephalopathy, which follows an X-linked dominant inheritance. The X - chromosomal mutations occur in both male and female embryos at the time of conception. In the former, however, guide you through hemizygosity almost always to intrauterine death. For this reason, almost exclusively girls with Rett syndrome was observed ( Gynäkotropie ). Was described for the first time Rett Syndrome in 1966 by the Viennese physician Andreas Rett ( 1924-1997 ). In Germany, the prevalence is estimated at 1:15,000 to 1:10,000.

In the DSM-IV diagnosis key Rett 's syndrome, Asperger's syndrome and are " unspecified pervasive developmental disorder " under a cipher 299.80 summarized. In ICD -10 Rett syndrome has its own paragraph F84.2.

Causes

In 1998, the cause of Rett syndrome could be located by scientists at the Baylor College of Medicine in Houston and Stanford University. They discovered a mutation in the MECP2 gene, thus enabling a very early can be used in the development of the child's genetic test ( applied since October 1999). This could make the diagnosis taking into account the above-mentioned criteria, safer, and it also could be even milder forms of Rett syndrome diagnose.

It is approximately 80 to 90 % of cases dominant de novo mutations of the X chromosome ( de novo mutation of the germline ) arising primarily in the male germ line and therefore passed on to the daughter mainly from father to ( get the children the Y chromosome from the father ).

Affected is the gene MeCP2 ( methyl -CpG - binding protein 2), which is located in the chromosomal region Xq28. MeCP2 is a transcriptional factor that selectively binds to methylated CpG islands and represses the transcription of various genes. Thus, the cholesterol metabolism is permanently disrupted.

An early onset, severe course of the disease can be triggered ( cyclin - dependent kinase -like 5 ) by a defect in the gene CDKL5, which is located in the region Xp22. This occurs in the first three months on a difficult to treat epilepsy.

Symptoms and complaints

The Viennese pediatrician Andreas Rett in 1965 discovered the typical hand movements ( washing movements, "washing movements" ) as two young girls in the waiting room of his practice sat on the lap of their mothers and they let go of the hands of their daughters by chance at the same time. This Handstereotypien regarded today as the most typical criteria for Rett syndrome. Over time, further diagnostic auxiliary criteria were added. The Austrian Rettsyndrom Society ( ÖRSG ) provides on its website prior to the following major criteria it.

Main criteria are:

  • Is followed by an initially normal development of the child between the 6th and 18th month first a standstill and then a significant regression. Acquired skills are unlearned, the normal use of the hands is lost.
  • Normal head circumference at birth. Slowing of skull growth between the 5th month and 4 years.
  • The language development occurs delayed or remains at an early stage stuck. Often the language is missing entirely.
  • Stereotypes of hands: washing movements at breast height or at the level of the mouth. Rhythmic movements of the upper body.
  • Severe cognitive disability, the actual intelligence is difficult to measure.
  • Unsafe, breitbeiniger gear. Often the ability to walk without assistance at all developed.
  • Diagnosis up to the age of 2 to 5 years.

In addition, a number of auxiliary criteria for Rett syndrome are listed which sometimes occur in the diagnosis but are not essential:

  • Irregularities in breathing
  • EEG - abnormalities with slowing of the background activity, epileptiform patterns and reduction of REM sleep ( the dream state )
  • Epileptic seizures ( at about 8 out of 10 people affected )
  • Poor circulation in the extremities
  • Gnashing of teeth
  • Scoliosis
  • Delayed growth
  • Increased muscle tone ( hypertonia ), especially in elderly people with Rett syndrome
  • Sleep

Stages of the disease

Hagberg and Witt - Engerström have created a general classification of the development of people with Rett syndrome, which is recognized worldwide and is divided into four stages. The details of the date and duration of each phase are given very different in different sources and thus represent only a guideline

At this stage, slowed motor development and it may come to a standstill. The gains had been made ​​in the development and learning of new things develop later and slower. With time, the attention of the children and activity decreases. The infant shows lack of interest in toys presented, the eye contact is also lower than in age-matched babies. The increase in head circumference is compared to the normal development back a bit. This phase can last several months.

  • Stage 2: Phase of regression (starts between 1 and 3 years )

It is characterized by a general regression of development. Already acquired skills (eg: functional use of the hands, tongue) are lost at this stage. In addition, the typical hand movements emerge ( washing, wrestling and clapping movements). The retrogression can suddenly and dramatically insert or delayed. These children are socially and emotionally withdrawn into itself, isolated, little can contact their environmental record and expire also in sudden cry phases. Through descriptions of children from their parents, it is believed that the girls at this stage lose the ability to grasp situations as a whole to set stimuli in relation to each other. Lindberg speaks in this context of disturbances of sensory perception and integration. " The signals from their own body and from the outside world seem to overwhelm and confuse, rather than to provide them with useful information." This disorder leads ( e) partly to the incorrect diagnosis of childhood autism. In this phase, it also comes the onset of epileptic seizures ( abnormal EEG). The duration of the second stage is described by several weeks and months.

  • Stage 3: Plateau stage (2nd -10 years of age. )

After the phase of rapid regression through girl with Rett syndrome is now a period of relative calm. There is a reduction in autistic traits, their behavior improved by reduced irritability and crying less. You begin to care for their environment again, with phases of attention with phases of the "in- itself - withdrawn -ness " alternate. The ability to communicate improved. Besides the already known symptoms such as teeth grinding, Handstereotypien and epileptic seizures remain. In addition, there will be increasing apraxia ( inability to perform learned neurological conveniently movements or actions, despite preserved perceptual and motor ability ) and ataxia ( neurological disorder of movement, these are unusual jerky ). ( → Development ) seizures occur in this phase often and Handstereotypien take. Gross motor skills are largely retained and degrade only slowly. This is clearly evident and the more uncertain gait.

  • Stage 4: Phase of motor deterioration (from about the age of 10 )

At this stage, the contact behavior opens even further. The frequency of attacks decreases, and the people affected with Rett syndrome show cognitive progress. " The gross motor skills rapidly deteriorate and weakness, emaciation, scoliosis, and spasticity force most girls to immobility and in a wheelchair. "

Cognition and Language

  • The most intensive communication facilities are undoubtedly the look and facial expressions.
  • According to estimates by parents and special educators girl with Rett syndrome are classified as highly cognitively disabled. However Dobslaff admits that it is very difficult to determine the exact cognitive development level with them.
  • Lindberg assumes that girls can classify different objects with Rett syndrome. The ability to organize and classify information is for recording, analysis and processing, sensory integration, of particular importance.
  • Dobslaff come to the conclusion that the girl with Rett syndrome only can classify them routine matters and things in familiar situations. For example, cups and plates are properly sorted apart.
  • The girls also recognize the personal property and differentiate between him and the other children, but they are overwhelmed when they have to classify different kinds of toys.
  • Girls with Rett syndrome have a problem with the transfer of lessons learned to new situations.
  • The girls can hardly remember performed actions when they demonstrated too fast or be repeated often enough.
  • Dobslaff represents the assumption that complex if-then relations ' can not be determined what the long term can lead to frustration among girls and women and possibly also explains her seemingly frequent disinterest.
  • Several authors confirm the object permanence and a strong understanding of symbol. People with Rett syndrome are aware of the representation of an image of an object and can do things / situations mostly seen in the original and copy. In addition, it is possible for them to interpret and associate images content.
  • In most cases, have the girls and women do not (more) via spoken language ( expressive language ). In contrast, their understanding of language ( receptive language ) is relatively complex.
  • Depending on the stage of Rett syndrome and individual skills is difficult to recognize communicative behavior. Often it seems that the girls are not able to make contact and communicate, at least there is no doubt that a serious communication impairment exists. In addition, they are inhibited by their motor impairments and their apraxia in their communication skills.

Consequences and complications

Rett syndrome leads to a lifelong, severe physical and mental disability. Children with Rett syndrome are permanently dependent on the help and assistance of others. The epileptic seizures can lead to falls and injuries. The motor difficulties, the uncertain transition, the increased muscle tension and scoliosis lead to limitations in mobility and immobility. The lack of language development complicates the understanding with the environment. These ( and other symptoms) make an autonomous and independent life impossible.

Treatment

There are no Rett syndrome healing therapy. Nevertheless, there are some therapies that are suitable for affected girls. However, these only help to influence some areas or sub- areas of multiple disabilities. Not all of the below featured therapy is appropriate for each child with this syndrome; here a consideration of the family situation as well as a professional advice plays an essential role. However, it is useful to combine individual therapies, however, to treat without the child.

  • Physiotherapy
  • Hippotherapy
  • Occupational Therapy
  • Other relevant for girls with Rett syndrome therapies Music Therapy
  • Speech Therapy
  • Hydrotherapy
  • Doman therapy
  • Augmentative and Alternative Communication
  • Petö
  • Speech Therapy - important for problems with eating and drinking
Locus (genetics) DNA methylation Medical diagnosis Chest Walking Perfusion Digital Object Identifier Integrated Authority File
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