Haematological parameters in erythropoietic protoporphyria: A multi-national study.

Erythropoietic protoporphyria (EPP) is a disorder of haem biosynthesis characterized by a reduction in ferrochelatase and subsequent accumulation of protoporphyrin IX. Haematological aberrations in EPP have been described, though they remain poorly understood. We present a detailed analysis of haematological parameters in EPP, drawing upon data from four large cohorts in the United States and Europe. We show an association between protoporphyrin levels and both platelet count and spleen size, and in a case-control analysis, we describe significant differences between haematological indices in EPP patients versus controls.