LE JEUNE SYNDROME ( J. J. L. M. Lejeune , fr. pediatrician and geneticist, sort. in 1926; synonym syndrome of cat's shout) — the inborn complex of malformations caused by disturbance of structure of one of chromosomes of group B. It is described in 1963 by Ge. Le Jeune et al. Frequency of a syndrome among newborns about 1: 3000, boys and girls equally often are surprised. The changes of a short limb of the 5th couple (fig. 1) arising more often owing to are the cornerstone of a syndrome deletions (see), is more rare — balanced translocations (see). At discrepancy of chromosomes in different cells in the first division meiosis (see) the chromosome which lost a part of genetic material it is unbalanced. In literature also other options of the balanced translocations in cells of parents leading to the birth of children with Hp are described.
Nek-raya variability the wedge, manifestations of a syndrome, apparently, depends on the sizes of the missing site of a chromosome. Children with Hp usually are born with a low weight (till 2500) even at the full-term pregnancy. The most constant sign, from to-rogo a syndrome received the name, the specific timbre of a voice reminding cat's miaow is. This symptom is caused by the features of a structure of a throat defined laringoskopichesk — a small sluggish epiglottis, tending to fall over a glottis; voice folds are not changed. Radiological reduction of the air space over voice folds is noted. With age the timbre of a voice is normalized, but often remains stridor (see) and tendency to inf. to diseases of upper respiratory tracts. At early age the round crescent-shaped face, a slanting section of eyes with the lowered outside corners, epikantus (a fold at an internal corner of an eye), the hypertelorism (widely placed palpebral fissures) which is a little flattened Nov, low located auricles, ahead of which often are available small (the size 1 — 3 mm), round fibrous small knots (fig. 2) is characteristic. A neurocranium of rather small sizes (nanocephalia) of a dolikhotsefalny form or with the acting frontal hillocks. Usually external features are supplemented with a small mandible and a short neck with the excess skin creating alate folds. In certain cases there can be a splitting of a lip (see. Lips ) or sky (see), or high Gothic sky and splitting of a uvula. Ophthalmolum, disturbances — passing or constant are possible squint (see), astigmatism of an eye (see). From anomalies of development of internals malformations of heart and vessels, kidneys are most frequent. At boys often happens hypospadias (see). Describe a chztyrekhpalost or short, triangular shape an average phalanx of the V finger. The general hypomyotonia characteristic of newborns with Hp, usually remains within a year and longer. Patients lag behind in psychomotor and physical. development. Biochemical, disturbances at Hp are not specific: long preservation of fetalis hemoglobin, a nek-swarm decrease in content of albumine in blood serum, a moderate aminoacidemia and an aminoaciduria. On both palms the cross furrow in most cases is defined, distal triradius is absent or its axis is in situation t (see. Dermatoglyphics ).
Average life expectancy of patients is reduced. Patients perish owing to a heart or renal failure, from intercurrent inf. diseases.
The syndrome follows to differentiate with other congenital anomalies of development of a chromosomal and not chromosomal etiology. The diagnosis is confirmed by a kariologichesky research using one of methods of identification of chromosomes of group B (an autoradiography, fluorescent dyes, etc.).
Treatment symptomatic. The means stimulating psychomotor development, massage, gymnastics are shown.
Prevention the births of children with Hp is based on definition of a karyotype of parents who had a sick child. Existence of the balanced translocation at one of them or mosaicism on deletion (5r —/5r) is the absolute indication for antenatal definition of a karyotype of a fruit at the subsequent pregnancies in the way amniocentesis (see) and researches of amniotic cells. The balanced translocation at one of parents demands also a research of a karyotype from his blood relatives for the purpose of identification of the persons having a trance a location.
Bibliography: Mladkovsky T. B., Lebedev B. V. and Mazayeva I. V. Syndrome of «cat's shout» (Cri du chat), Geneticist, t. 6, No. 10, page 125, 1970, bibliogr.; L e j e-u n e J. e. a. Trois cas de deletion partielle du bras court d’un chromosome 5, C. R. Acad. Sci. (Paris), t. 257, p. 3098, 1963; Pfeiffer R. A. Karyotyp und Phanotyp der autosomalen Chromosomen-aberrationsen beirn Menschen, Stuttgart, 1968; Valentine G. H. The chromosome disorders, Philadelphia, 1969.
L. O. Badalyan.