Study of the prevalence of osteogenesis imperfecta and Ehlers-Danlo syndrome in the Republic of Bashkortostan

BACKGROUND: Osteogenesis imperfecta (Q78.0) and Ehlers-Danlo syndrome (Q79.6) are rare inherited (orphan) connective tissue diseases with variable clinical manifestations and a wide range of molecular defects. Data on the prevalence of these diseases are fragmentary due to the heterogeneous clinical picture and low availability of molecular diagnostics both in the world and in Russia. However, understanding the frequency of these diseases may help to optimize diagnosis and improve the quality of medical care for this category of patients. AIM: To analyze the prevalence of osteogenesis imperfecta and Ehlers-Danlo syndrome in the Republic of Bashkortostan according to medical records. MATERIALS AND METHODS: Data on the population of the republic were obtained from the official website of the Federal State Statistics Service for the Republic of Bashkortostan. Information on the incidence of diseases was taken from the reports of the Medical Information and Analytical Center of the Republic of Bashkortostan, analysis of the card file of the Republican Medical and Genetic Center (Ufa) and analysis of the Republican Medical Information and Analytical System «ProMed». Molecular genetic studies were performed by massively parallel sequencing. RESULTS: A total of 199 patients with osteogenesis imperfecta have been identified in the Republic of Bashkortostan, 69 (34.6%) of them are under active observation. Molecular genetic study was performed for 64 patients (32.1%), and 16 pathogenic changes in the COL1A1 gene, 11 pathogenic mutations in the COL1A2 gene, one mutation each in the P3H1 and IFITM5 genes were detected. 112 males and 87 females were identified. The share of patients under 18 years of age in the whole republic amounted to 36.1%. In Ufa 80 patients were registered, the percentage of patients under active surveillance amounted to 42.5%. In general, 133 patients with Ehlers-Danlo syndrome were registered in the Republic of Bashkortostan, of which 30 patients (22.5%) were under active surveillance. Molecular genetic study was carried out in 43 patients (32.3%), and 5 changes of nucleotide sequence in the COL5A1 gene and 3 in the COL5A2 gene were revealed. There were 71 men and 62 women. As in the case of LE, patients older than 18 years prevail — 89 patients (66.9%), 18 patients (28.6%) were under active surveillance. The overall prevalence of osteogenesis imperfecta in the Republic of Bashkortostan amounted to 5.031 cases per 100,000 population, Ehlers-Danlo syndrome — 3.362 cases per 100,000 population. Patients with osteogenesis imperfecta are more often on active follow-up compared to Ehlers-Danlo syndrome (48.6% and 22.5%, respectively), which is explained by a longer period of work with this group of patients. CONCLUSION: The prevalence of osteogenesis imperfecta and Ehlers-Danlo syndrome in the Republic of Bashkortostan according to medical records was determined. The total prevalence of osteogenesis imperfecta in the Republic of Bashkortostan amounted to 5.031 cases per 100 thousand population, Ehlers-Danlo syndrome - 3.362 cases per 100 thousand population.