Epidemiology of acquired aplastic anemia in children in the Russian Federation

Although acquired aplastic anemia (AA) remains a rare disease worldwide, the incidence of acquired AA in different countries varies widely. This article presents the results of an epidemiological study of acquired AA in children in the Russian Federation. The study was approved by the Independent Ethics Committee and the Scientific Council of the Dmitry Rogachev National Medical Research Center of Pediatric Hematology, Oncology and Immunology of Ministry of Healthcare of the Russian Federation. In this study, we analyzed the epidemiological data of patients aged 0 to 18 years with acquired AA who had been diagnosed remotely at the laboratories of the Dmitry Rogachev National Medical Research Center of Pediatric Hematology, Oncology and Immunology from September 1, 2017 to December 31, 2023 as part of the first registry study conducted in Russian Federation. Our analysis included data from 582 patients from 77 regions of the Russian Federation; the coverage of the pediatric population was 97%. The average incidence rate for the 6-year period was 3.1 cases per 1 million children per year. The median age was 10.2 years (range 1–17.9 years). Most cases of acquired AA occurred between the ages of 5 and 9 years and between 10 and 14 years. There were no cases of acquired AA in children under the age of 1 year. There were more males than females: 317 (54.5%) versus 265 (45.5%). According to etiology, 87% of the patients were diagnosed with idiopathic AA, and 13% had hepatitis-associated AA. In total, 45.7% of the patients fulfilled the criteria for very severe AA, 38.8% for severe AA, and 15.5% for non-severe AA. Paroxysmal nocturnal hemoglobinuria clone was detected in 42.3% of the patients with acquired AA. The incidence rate of acquired AA in children in Russian Federation is intermediate between the European and Asian incidence rates. Our main demographic data and disease characteristics are consistent with the world data.