protoporphyria Erythropoiesis and iron metabolism in dominant erythropoietic

ABSTRACT Erythropoietic protoporphyria (EPP) results from deficiency of ferrochelatase (FECH) Accumulation of protoporphyrin IX causes life-long acute photosensitivity. Microcytic anemia occurs in 20 – 60% of patients. We investigated 178 patients with dominant EPP confirmed by molecular analysis. Erythropoiesis was impaired in all patients; all had a downward shift in haemoglobin (Hb), the mean being decreased in males by 1.2g/dL. By WHO criteria, 48% of women and 33% of men were anemic. Iron stores, assessed by serum ferritin (sFn), were decreased by two-thirds but normal serum soluble transferrin receptor-1 and iron concentrations suggested that erythropoiesis was not limited by iron supply. FECH deficiency in EPP appears to lead to a steady state in which decreased erythropoiesis is matched by reduced iron absorption and supply. This response may in part be mediated by protoporphyrin but we found no correlation between erythrocyte protoporphyrin and Hb, sFn, total iron binding capacity or transferrin saturation. From bloodjournal.hematologylibrary.org by guest on June 12, 2013. For personal use only.