Clinical and Epidemiological Characteristics of Tuberous Sclerosis in The Republic of Bashkortostan

Relevance. Tuberous sclerosis (TS) is a hereditary tumor syndrome with autosomal dominant type of inheritance, occurring with frequency of 1:6000 — 10000 newborns worldwide. The disease is characterized by severe clinical manifestations in the form of astrocytomas of the brain, rhabdomyomas of the heart, angiomyolipomas of the kidneys, pulmonary lymphangioleomyomatosis and angiofibromas of the skin. Since effective treatment with mTOR inhibitors has been developed for TS, timely detection of patients with TS is important. The aim of the study. To determine the frequency and clinical features of TS in the Republic of Bashkortostan to improve organizational and therapeutic and diagnostic approaches in providing medical care to patients with TS. Material and methods. Determination of clinical and epidemiological features of TS in the Republic of Bashkortostan. Results. In the Republic of Bashkortostan, 86 patients with TS from 82 families were registered, the frequency of occurrence was 1:47048 people. The average age of patients was 18.5 years (from 1 year to 61 years). Depigmentation spots were found in 90 % of patients, facial angiofibromas in 56 %, head fibrous plaques in 33 %, shagreen plaques in 36 %, subependymal nodules of the brain in 66 %, and subependymal giant cell astrocytoma in 19 %, renal angiomyolipomas in 43 %, pulmonary lymphangioleiomyomatosis in 1.2 % of patients. Cognitive deficit was found in 47 %, epilepsy in 67 %, and autism in 1 % of patients with TS. Discussion. Comparative analysis of TS clinical manifestations in patients from the Republic of Bashkortostan with global data showed a significantly lower incidence of facial angiofibromas, lungs, kidneys and brain tumors, cognitive impairment and autism. 8 patients with identified mutations in the TSC1/TSC2 genes are treated with an mTOR inhibitor. Conclusion. The obtained results indicate a low frequency of registered cases of TS in the republic compared to world data. Therefore it is necessary to familiarize doctors of all specialties with the need to refer patients with symptoms characteristic of TS for medical genetic consultation. For reliable detection of tumors of the brain and internal organs, dynamic instrumental studies are necessary; assessment of psychological disorders in TS patients is necessary with consultation of psychotherapists, neurologists and psychologists.

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