Hereditary erythrocytosis in the Chuvash Republic. À literature review

The purpose of this review is to update information about the epidemiology, clinical-pathogenetic and genetic characteristics, and therapeutic approach to familial inherited erythrocytosis (FIE) in children in the Chuvash Republic. This review presents updated data indicating that the variant of congenital polycythemia with the VHLR200W (598C>T) mutation in the Chuvash Republic does not have the expected association with tumor predisposition syndrome induced by VHL and does not lead to an increased frequency of their occurrence. Thrombosis largely explains the morbidity and mortality from congenital erythrocytosis, but patients with the Chuvash mutation show a reduced body mass index, systolic blood pressure levels, glucose and HbA1c levels, and leukocyte and platelet counts compared to control groups. A higher hematocrit level is not an independent predictor of thrombotic risk in children and adults. Moreover, prospective randomized studies have demonstrated that phlebotomy, performed to reduce hematocrit levels, is associated with a higher thrombotic risk.