Prevalence of C282Y, H63D and S65C gene mutations in patients with hyperferritinemia undergoing therapeutic phlebotomy suspected of having hereditary hemochromatosis

Abstract

Background: Hemochromatosis is an autosomal recessive disorder caused by excessive iron overload in parenchymal organs. In Brazil, the prevalence of hereditary hemochromatosis (HH) may vary compared to other countries due to different ethnical backgrounds according to the geographic region studied. The prevalence of C282Y mutation of the HFE gene ranges from three to eight times lower in Brazilians than in Caucasians of Northern European origin. Methods: A retrospective cross-sectional study was carried out in 222 patients submitted to therapeutic phlebotomy between March 2011 and July 2014 in a tertiary hospital blood center. The prevalence of HH was determined in 89 (47.3%) out of 188 (84.6%) patients presenting hyperferritinemia, and divided in two genotype groups: C282Y mutation and other mutations. The HH patients’ geographical and clinical characteristics, serum ferritin rate (SF) and transferrin saturation (TS) were analyzed. Results: The HH group consisted of 71 males (79.7%) and 18 (20.3%) females, with a median age of 51.5 ± 10.6 years. There were 36 (40.0%) symptomatic patients and 65 (73.0%) tested positive for the HFE mutation. The initial baseline TS values were significantly higher in primary HH patients (48.6%, IC 95% 43.2% - 55.7%) compared to those with secondary HH (35.0%, IC 95% 27.5% 41.8%, p=0.001). Conclusion: The prevalence of C282Y mutation was higher in this population from the South region compared to previous reports in the Brazilian population, yet inferior to that of Northern Europeans.