Laron's syndrome: causes, diagnosis, treatment, prognosis

Laron's syndrome is a pathological condition in which the body is unable to perceive and use growth hormone. The most common sign of this violation is dwarfism. Other symptoms include muscle weakness and decreased endurance, childhood hypoglycemia, delayed sexual development, limb shortening, and obesity. Most often pathology causes changes (mutations) of the gene responsible for growth. It is inherited by an autosomal recessive trait.

Symptoms

Laron's syndrome is a fairly rare disorder. With this diagnosis, newborn babies tend to have average statistical growth and weight, but later on their physical development slows down dramatically. In the absence of treatment, adult men reach a maximum height of 130 cm. The height of women does not exceed 120 cm.

In addition to low growth, pathology is indicated by the following symptoms:

• Weakness in muscles, insufficient endurance;
• Hypoglycemia in childhood;
• Delay in puberty;
• Disproportionately small genitals;
• Thin, weak hair;
• Disorders of the structure of the teeth;
• Shortened limbs;
• obesity;
• Distinctive features of the face (protruding forehead, fallen nose, blue scleral syndrome).

Causes

Laron's syndrome causes mutations of a gene containing a growth hormone receptor - a protein located on the outer shells of cells throughout the body. The growth hormone receptor is designed to recognize and activate somatotropin, thereby initiating cell growth and division. Mutations of the gene interfere with the normal functioning of this biological mechanism and lead to violations of cellular development. Many symptoms of the pathology are caused by the inability to produce a secondary hormone, an insulin-like growth factor.

Heredity

In most cases, Laron's syndrome in children is inherited by an autosomal recessive type. This means that the disorder is caused by mutations in both copies of the affected gene in each cell. Parents of a patient with a pathology are usually carriers of one mutated copy of the gene and very seldom suffer from typical manifestations of the disorder. When a child is born to two carriers of an autosomal recessive disease, the risk of inheriting pathology is 25%; The probability of becoming a passive carrier, like each of the parents, is 50%; A chance not to inherit either pathology or a mutated gene - 25%.

According to some reports, there are families in which Laron's syndrome is inherited by an autosomal dominant type. In such cases, a mutation in one copy of the affected gene in each cell is sufficient to transmit the disease. Sometimes on this basis the child adopts a pathology from a sick parent. There are also cases of new, non-hereditary genetic mutations, when the disorder is diagnosed in children whose families did not have a single case of the disease. A person with confirmed pathology transmits a mutated gene to their children in 50% of cases.

Diagnostics

Already after the initial assessment of obvious signs and symptoms, a specialist can diagnose Laron's syndrome (photos of people with pathology see in the article). To confirm this diagnosis and effective differentiation, additional examinations are carried out, including a blood test for specific hormones. More often in people with this disorder, there is an increase in the level of somatotropin simultaneously with a decrease in the insulin-like growth factor. In some cases, doctors prescribe genetic studies to confirm the fact of gene mutation. The results of diagnostic measures allow you to accurately determine the Laron syndrome.

Treatment

To completely cure this pathological condition, modern medicine is not yet able. Innovative therapy is primarily focused on accelerating growth, which is provided by the method of hypodermic injections of the missing insulin-like hormone. The substance stimulates linear growth (in height), accelerates the development of the brain and prevents the emergence of metabolic disorders caused by a protracted deficiency of the necessary proteins. In addition, such injections raise the level of sugar in the blood, prevent the accumulation of cholesterol and significantly tone up the muscle tissue. Treatment with insulin-like growth factor should be carried out under the vigilant supervision of specialists, as exceeding the required dosage can lead to serious health problems.

Forecast

The long-term outlook is often optimistic enough. Laron's syndrome in no way affects life expectancy. Moreover, carriers of this hereditary pathology are much less at risk of oncological diseases and insulin-independent diabetes mellitus. At present, extensive studies are under way to identify the links between Laron's syndrome, genetic mutations, growth hormone and the development of malignant tumors. It is possible that it is in such genetic alterations that the key to victory over cancer lies.