Prader-Willi syndrome

The Prader-Willi syndrome is a rare genetic pathology, the type of hereditary transmission of which has not been established to date. For the first time the Prader-Willi syndrome was described in 1959 by the Swiss pediatricians H. Willi and A. Prader, who owes their name. This pathology is also called the syndrome of three "hypo" (hypotonia, hypogonadismus, hypomentia): muscle hypotension, dementia and hypogonadism. In addition, in the clinical picture there is a small growth and acromycery - a small size of the hands and feet. This disease is a complex of hereditary anomalies that are transmitted by autosomal recessive type, the syndrome is most often found sporadically, but there are data on family cases. As a rule, cytogenetic studies of deviations do not reveal.

For this pathology, a combination with such diseases as severe mental retardation with cerebral obesity, small growth, hypogenitalism and dysplastic phenomena is typical. Great importance in the pathogenesis of this disorder is attributed to hypothalamic dysfunction. Effective methods of prevention and specific treatment of the Prader-Willi syndrome do not exist now.

There are two phases in the development of the disease. Soon after birth, the child has severe muscle hypotension. Symptoms are so severe that babies can not perform spontaneous movements and, worst of all, can not suck, so they have to be fed from a pipette or through a probe. The result of severe muscle hypotension is the delay in the formation of locomotor and static functions - children can not hold their heads, sit, etc. In addition, there is a tendency to hypothermia.

The development of the next stage occurs in a few weeks (months), usually towards the end of the first-beginning of the second year of life. Symptoms of hypotension decrease, and bulimia develops, in which children experience a constant feeling of hunger, actively looking for food. As a result, obesity begins to develop, which has a very characteristic form of distribution of subcutaneous fat - most of it is located on the proximal limbs (thighs and shoulders) and the trunk, resulting in the hands and feet becoming disproportionately small. In addition, in this phase of the disease, mental retardation manifests itself: speech becomes difficult, the vocabulary becomes extremely limited. Characteristic of the emergence of hypogonadism: in boys it manifests itself in the hypoplasia of the penis, in girls - in the hypoplasia of the labia. In most cases, Prader-Willi syndrome is accompanied by diabetes mellitus.

The basis for the diagnosis of this pathology is the identification of a complex of typical symptoms, as cytogenetic studies and karyotyping do not reveal any peculiarities. It is accepted to distinguish two main groups of clinical signs: those observed from the moment of birth to three years and manifesting at the age of more than three years. The first group of signs include: low birth weight, muscle hypotension, and difficulty feeding. Quite often mothers note very weak, hardly noticeable movements of the fetus in the perinatal period. Sometimes up to six months of age there is increased drowsiness, attacks of lethargy and apnea. Characteristically delayed psychomotor development and dysmorphia (almond-shaped eye, broad bifrontal diameter and lowered corners of the mouth).

Prader-Willi syndrome has some phenotypic similarity to such a congenital disease as hypothyroidism, which is also characterized by muscle hypotension, excessive fat deposition in typical places, growth retardation and psychomotor development.

In view of the presence of a multitude of a wide variety of diseases, receiving their name for the first time described by their scientist, there is some confusion. Quite often Pruder-Willy syndrome is called as "Willie Brandt's disease", although the disease has absolutely nothing to do with the German policy of Willy Brandt, who was the fourth Federal Chancellor of Germany (1969-1974).