Iron Deficiency in Patients with Paroxysmal Nocturnal Hemoglobinuria: A Cross-Sectional Survey from a Single Institution in China.

BACKGROUND Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired clonal hematopoietic disorder that often manifests with chronic intravascular hemolysis. Iron deficiency in patients with PNH is most often due to urinary losses of iron secondary to chronic intravascular hemolysis. MATERIAL AND METHODS This cross-sectional survey assessed the prevalence of iron deficiency in a Chinese population of PNH patients who were enrolled between May 2012 and October 2014. RESULTS A total of 742 PNH cases were selected by FLARE and classified as classical PNH (15.36%), PNH in the setting of another specified bone marrow disorder (12.26%), and subclinical PNH (72.38%). The median age of all the patients was 32 years (range 5-77 years). The overall prevalence of iron deficiency was 17.9% among all the PNH patients enrolled in the survey, 76.3% (87/144) among those with classical PNH, 33.0% (30/91) among those with PNH in the setting of another specified bone marrow disorder, and 3.0% (16/537) among the subclinical PNH patients. The incidence of iron deficiency among classical PNH patients was higher than that in the other 2 subcategories (P-value=0.000). Multivariate analyses showed that age and disease duration were independent risk factors for iron deficiency in classical patients. CONCLUSIONS This survey shows that PNH patients were prone to iron deficiency, especially patients with classical PNH.