Clinical Characteristics of Neurofibromatosis Type 1 in the Republic of Bashkortostan

Relevance. Neurofibromatosis type 1 (NF1) is a hereditary tumor syndrome occurring with a frequency of 1:3164 of the world’s population. The disease is characterized by severe clinical manifestations such as multiple cutaneous and subcutaneous tumors, plexiform neurofibromas, skeletal abnormalities, cognitive disorders and various complications. The aim of the study. To determine the frequency of NF1 in the Republic of Bashkortostan and its dynamics, clinical features of NF1 to improve organizational and therapeutic and diagnostic approaches in providing medical care to patients with NF1.Material and methods. A clinical and epidemiological study of NF1 patients in the Republic of Bashkortostan and a comparative analysis with data for 2009 and 2021 were conducted. Results. In the Republic of Bashkortostan, 544 patients with NF1 from 433 families aged 1 to 85 years (average age 30 years and 7 months) were registered, the incidence rate is 1:7407 people. Pigment spots were identified in all patients, cutaneous and subcutaneous neurofibromas in 58 %, plexiform neurofibromas in 7 %, scoliosis in 17.4 %. Learning difficulties were identified in 14 %, epilepsy in 3.7 %, hydrocephalus in 4 %, optic nerve gliomas in 6 %, and brain tumors in 4 % of NF1 patients from the republic. Discussion. A comparative analysis of the characteristics of NF1 in patients from the Republic of Bashkortostan with global data showed a significantly rarer detection of neurofibromas, Lisch nodules, optic nerve gliomas, intellectual disabilities and psychological disorders. The number of patients with NF1 in the republic has increased by 2.3 times in 15 years and by 35 % in the last 3 years. Moreover, 4 patients with plexiform neurofibromas are receiving a mitogen-activated protein kinase inhibitor, which has proven its effectiveness. Conclusion. The obtained results indicate an increase in the number of registered cases of NF1 in recent years, but the need for a multidisciplinary approach in the study of patients due to the reliably low frequency of registration of characteristic symptoms of the disease.

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