Turner syndrome

Turner syndrome: description

Turner Syndrome is also referred to as Monosomy X. It occurs in 1 in 2,500 newborns. Women with Turner syndrome lack functioning ovaries. Turner syndrome is referred to as a syndrome because there are several signs of the disease that occur and are related at the same time. It is also called a symptom complex.

The Turner syndrome symptoms were already in 1929 by the German pediatrician Otto Ullrich and 1938 by the American doctor Described by Henry Turner. Therefore, the name Ullrich-Turner syndrome (UTS) is also used for the disease. But only in 1959 was it possible to find the missing sex chromosome as the cause.

Monosomy X is relatively common. It is assumed that every tenth spontaneous abortion in the first trimester of pregnancy is caused by them. Overall, 99 percent of fetuses die with the chromosome set “45, X0” during pregnancy.

Turner syndrome: symptoms

Patients with Turner syndrome are always female. The Turner Syndrome features are diverse and do not always fully affect all patients. In addition, they are age-related, which means that some symptoms appear before or shortly after birth, while other signs appear in the next CV.

While some symptoms may be weak or absent, a short stature of 148 cm is typical of Turner syndrome.

Turner syndrome patients are common in all stages of life

• shortened middlehand bones
• a deep-seated hairline and a widened skin fold on the side between neck and shoulders (wing-skin, pterygium colli)
• Malformations of internal organs: z. B. Heart defects (including aortic coarctation, atrial septal defect) or renal malformations (eg horseshoe kidney)

Age-related Turner syndrome symptoms

Newborns are often affected by lymphoedema on the backs of the hands and feet. These are accumulations of fluid in the skin caused by defective lymphatics.

Infants with Turner syndrome often have the following symptoms:

• wide and flat thorax (Schildthorax) with widely spaced nipples
• many liver spots (nevi)
• incipient osteoporosis (bone loss)

In adolescence, the hypofunction of the ovaries is noticeable. If ovaries are present, they form back further and further. Usually, however, only strands of connective tissue (streak gonads) are present from the beginning. This leaves puberty off. Girls with Turner syndrome do not have menstrual bleeding. Physicians also speak of a primary amenorrhea.

Other Turner syndrome features

Other signs of Turner syndrome include:

• Ear malformations
• hardness of hearing
• Underdeveloped (hypoplastic) genital

The mental development in patients with Turner syndrome is usually normal. However, hearing problems can occur at school due to deafness.

Turner syndrome: causes and risk factors

Turner syndrome: word explanations

To better understand the Turner syndrome, here are some explanations.

Turner syndrome is based on chromosome aberration. This is understood by physicians that the number or structure of the chromosomes is disturbed. On the chromosomes are stored our genetic information. Normally there are 46 chromosomes in each cell. These include two sex chromosomes. In the female karyotype (chromosome set), they are referred to as XX, in the male as XY. A normal karyotype is described as 46, XX, or 46, XY, respectively. If a chromosome is missing, this is called a monosomy.

Turner syndrome: various karyotypes

Different karyotypes can lead to Turner syndrome:

• 45, X0: Approximately 50% of sufferers have only 45 instead of 46 chromosomes in all body cells. It lacks a sex chromosome (X or Y). This is called Monosomy X.
• 45, X0 / 46, XX or 45, X0 / 46, XY: In more than 20% of patients, both cells with complete set of chromosomes (46, XX) are present, as well as cells with monosomy X (45, X0). This is called mosaic
• 46, XX: About 30% of those affected have a complete set of chromosomes in all cells (46, XX), but one X chromosome is structurally altered

How is monosomy X created?

It is believed that the cause of Turner’s syndrome is the maturation of the father’s sperm. This is justified by the fact that studies show that the present X chromosome was inherited by the mother in almost 80 percent of the cases.

Parents of a child with Turner syndrome have no increased risk that another child is also suffering. In addition, the age of the mother is not considered a risk factor for the development of a Turner syndrome.

Turner syndrome: examinations and diagnosis

Turner syndrome can be diagnosed at different times. Often infants fall first by their short stature, so that the pediatrician causes further investigation. As the disease progresses, gynecologists and human geneticists also play a role. If your pediatrician suspects a Turner syndrome, he first asks you in detail about the history of the disease (anamnesis). Among other things, he may ask the following questions:

• Are hereditary diseases known in your family?
• Was your child always smaller than the same old playmates?
• Did you notice any swollen hands or feet in your baby at birth?

Turner syndrome: physical examination

The main focus is on the physical examination of Turner’s syndrome on the inspection. The pediatrician looks closely at individual parts of the body and pays attention to abnormalities such as short metacarpal bones, pterygium colli, liver spots (nevi), thoracic shape, nipple distance and body size.

During auscultation, the doctor can detect any cardiac malformation. With the ultrasound malformations of the kidney can be detected.

Turner syndrome: blood test

After a blood sample, various hormone levels can be determined in the laboratory. Patients with Turner syndrome usually have high FSH and LH levels and very little estrogen in their blood.

In addition, the collected blood cells can be viewed under a microscope and the number and structure of the chromosomes can be analyzed. Thus, the monosomy X can be easily recognized because there is only one instead of two sex chromosomes.

Turner syndrome: prenatal examinations

By means of prenatal examinations (prenatal diagnosis) the Turner syndrome can already be detected in children in the womb. That succeeds about with invasive procedure such as amniocentesis (Amniocentesis) or a study of the mother cake (Chorionzottenbiopsie). Their disadvantage, however, is an increased miscarriage risk, because an intervention in the pregnant woman is necessary for the sampling (removal of amniotic fluid or a sample of the placenta).

Have this disadvantage non-invasive prenatal blood tests like the Harmony test, PraenaTest and Panorama test not. For these examinations, only one blood sample of the pregnant woman is needed. In it can be found traces of childhood genetic material that can be examined for chromosomal abnormalities such as Turner’s syndrome. The test result is quite reliable. However, depending on the test and the scope of the analysis, such an examination costs several hundred euros, in addition to the costs of the necessary medical services (such as genetic counseling and blood sampling). All pregnant women usually have to pay for this themselves. Health insurance companies only pay for the costs in individual cases.

Turner syndrome: treatment

To treat the dwarfism, a therapy with growth hormones should be started already in infancy. In this way, a length increase of 5 to 8 centimeters can be achieved. For this purpose, the growth hormone must be injected daily into the subcutaneous fat tissue (subcutaneously).

At the age of 12 to 13 years should be initiated by an experienced child endocrinologist or pediatric gynecologist puberty by medication. For this, estrogen supplements are taken daily for 6 to 18 months. Subsequently, a normal four-week cycle is established in which estrogens are taken for 3 weeks, which are then paused for 1 week.

The dwarfism and the lack of puberty are often very stressful for Turner syndrome patients, so that the mentioned therapies can increase the well-being. In addition, the estrogens help counteract early-onset osteoporosis.

Turner syndrome: disease course and prognosis

The karyotype underlying Turner syndrome influences the symptom severity and prognosis in part considerably:

In patients with Ullrich-Turner syndrome, who have a 45, X0 chromosome set in all cells, puberty does not occur because the ovaries do not produce sex hormones. Physicians also speak of primary ovarian failure. These patients are infertile.

Patients with a mixed karyotype with proportions of Y chromosome (45, X0 / 46, XY) are at risk of developing ovarian degeneration (gonads) into gonadoblastoma. In these patients, a precautionary removal of the ovaries should be considered.

Patients with a set of mosaic chromosomes may have normal puberty with a regular menstrual cycle. Pregnancy is possible.

Turner syndrome: risk of other diseases

In adulthood Turner syndrome patients are at an increased risk

• Hypertension (arterial hypertension)
• Diabetes mellitus
• Obesity (obesity)
• Osteoporosis (frailty of bones)
• Thyroid disorders (Hashimoto’s thyroiditis)
• Bleeding of the digestive tract (gastrointestinal bleeding)

to get sick. Therefore, health checks should be carried out regularly in order to detect and treat the diseases as early as possible.

Turner syndrome: pregnancy

If pregnancy is possible, the risk to the life of the mother and child should be discussed with an experienced gynecologist. During pregnancy, a Turner woman is 100 times more likely to suffer a rupture of the main artery (aortic rupture or dissection) compared to healthy women. In addition, the likelihood of pregnancy-related diabetes and hypertension is increased. The frequencies of preterm delivery, stillbirth and growth retardation (intrauterine growth retardation) in maternal Turner syndrome are increased.