Shereshevsky-Turner Syndrome

Turner's syndrome (Shereshevsky-Turner syndrome, Bonnevi-Ulrich syndrome, Syndrome 45, X0) is a consequence of the complete or partial absence of one of the two sex chromosomes, the female sex is phenotypically determined. The diagnosis is based on clinical manifestations and is confirmed by the study of a karyotype. Treatment depends on the manifestations and may include surgical treatment for heart defects, and often therapy with growth hormone in case of short stature and estrogen replacement therapy in the absence of puberty.

Clinically, it was first described by the local endocrinologist NA Shereshevsky in 1926. The cytogenetically syndrome was verified in 1959. The population frequency is 1: 5000 female.

[1], [2],

Epidemiology of Shereshevsky-Turner syndrome

Shereshevsky-Turner syndrome occurs at a frequency of about 1/4000 live births and is the most common anomaly of sex chromosomes in women. At the same time, 99% of pregnancies with karyotype of fetus 45, X result in spontaneous abortion.

[3], [4], [5], [6]

What causes the Shereshevsky-Turner syndrome?

Approximately 50% of patients with Shereshevsky-Turner syndrome have a karyotype of 45, X; in about 80% of cases the paternal X chromosome is lost. Most of the remaining 50% is mosaic (for example, 45, X / 46, XX or 45, X / 47, XXX). Among mosaic patients, the phenotype may vary from the typical for Turner syndrome to normal. Sometimes girls with Shereshevsky-Turner syndrome may have one normal X-chromosome and one X-ring chromosome; in order for the ring chromosome to form, it must lose the area from the short and long arms. Some girls with Turner syndrome can have one normal Chromosome and one isochromosome consisting of two long arms of the X chromosome, which was formed after the loss of the short arm. These girls tend to have many of the phenotypic traits of Turner's syndrome; thus it seems that the division of the short arm of the X chromosome plays an important role in the formation of the phenotype of the Shereshevsky-Turner syndrome.

Pathogenesis of Shereshevsky-Turner syndrome

The absence or alteration of the sex chromosome leads to a disruption in the maturation of the ovaries, the absence or late partial sexual maturation and infertility.

Symptoms of Shereshevsky-Turner syndrome

Many newborns have only very mild manifestations; but some have marked dorsal lymphedema of the hands and feet, as well as lymphedema or skin folds on the posterior surface of the neck. Other common anomalies include the pterygoid folds of the neck, the broad thorax and the retracted nipples. The affected girls have a low growth rate compared to family members. Less common signs are a low line of hair growth on the back of the neck, ptosis, multiple pigmented nevuses, short fourth metacarpal and metatarsal bones, protruding pads of fingers with curls at the ends of the fingers, and hypoplasia of the nails. Also marked cubitus valgus (valgus deviation in the elbow joint).

Common heart abnormalities include coarctation of the aorta and a two-fold aortic valve. Often with age, hypertension develops, even in the absence of coarctation. Quite often there are abnormalities of the kidneys and hemangiomas. Sometimes in the digestive tract, telangiectasia is detected, with developing gastrointestinal bleeding or loss of protein.

Gonadal dysgenesis (the ovaries are replaced by bilateral strands of the fibrous stroma with the absence of developing reproductive cells) is noted in 90% of patients, leading to the absence of puberty, the absence of enlargement of the mammary glands, amenorrhea. At the same time, 5-10% of affected girls spontaneously develop menarche, and very rarely affected women are fertile and have children.

Mental retardation is rare, but many patients experience a reduction in some perceptual possibilities and, as a result, low scores in nonverbal tests and in mathematics, even though the scores obtained for the verbal component of the intelligence tests are average or even high.

• Growth retardation, often from birth (100%).
• Gonadal dysgenesis with amenorrhea and sterility.
• Lymphatic edema of the rear of the hands and feet (40%).
• Broad chest with combined sternum deformity.
• Widely placed, hypoplastic and inverted nipples (80%).
• Anomalous in shape and protruding ears (80%).
• Low level of hair growth.
• Short neck with excess skin and pterygoid folds (80%).
• Cubitus valgus (70%).
• Narrow, hyper-concave and depressed nails (70%).
• Congenital malformations of the kidneys (60%).
• Hearing loss (50%).
• Congenital heart and aortic defects (coarctation of the aorta and valve pathology, enlargement and dissection of the aorta) (20-40%).
• Idiopathic arterial hypertension (AH) (27%).

Diagnosis of Shereshevsky-Turner syndrome

In newborns, the diagnosis can be suspected in the presence of lymphedema or the pterygopalatinal fold of the neck. In the absence of these changes, the diagnosis in some children is later revealed on the basis of low stature, amenorrhea and absence of puberty. The diagnosis is confirmed by the study of a karyotype. Echocardiography or MRI is indicated for the detection of congenital heart defects.

Cytogenetic analysis and studies with a Y-specific probe are performed for all persons with gonadal dysgenesis to exclude mosaicism with the presence of a cell line with karyotype 46, XY (45, X / 46XY). These patients usually have a female phenotype with different traits of Turner's syndrome. They are at a high risk of developing malignant gonadal tumors, especially gonadoblastoma, so for the prevention immediately after the diagnosis is determined, remove the gonads.

[7], [8], [9], [10], [11]

Physical Examination

The diagnosis is based on a characteristic clinical picture: a short neck with excess skin and pterygopalatine folds in newborn girls, lymphatic edema of the hands and / or feet, congenital malformations of the left heart or aorta (especially aortic coarctation ), delay in growth and puberty in girls .

Laboratory research

Cytogenetic research verifies the absence of the X chromosome or its structural changes.

Treatment of Shereshevsky-Turner syndrome

There is no specific treatment for genetic disorder. Coarctation of the aorta is usually treated promptly. Other heart defects show dynamic observation and surgical correction if necessary. With lymphedema apply compression stockings.

Therapy with recombinant human growth hormone can begin if growth is less than 5 percentiles, the initial dose is 0.05 mg / kg subcutaneously once a day. Typically, at the age of 12-13 years for the initiation of pubertal, estrogen replacement therapy is required in the form of conjugated estrogens of 0.3 mg orally or of micronized estradiol, 0.5 mg once a day. After this, oral contraceptives containing progestin are prescribed to maintain secondary sexual characteristics. Growth hormone continues to be administered together with sex hormone therapy before the growth zones close, when growth hormone therapy is discontinued. Continuation of hormone replacement therapy helps to achieve optimal bone density and skeletal development.

Shereshevsky-Turner syndrome is treated with the help of correction of short stature by conducting courses of human somatropin, and also the formation of secondary sexual characteristics by the appointment of estrogens.

What is the prognosis of Shereshevsky-Turner syndrome?

Syndrome Shereshevsky-Turner has a favorable for life and intellectual development forecast. Unfavorable for procreation.