Abstract

Background Paroxysmal Nocturnal Hemoglobinuria (PNH) pathogenesis is due to acquired lack of glycosylphosphatidylinositol-anchored protein complement regulatory proteins (CD55 and CD59) and intra-extravascular hemolysis. Eculizumab is a monoclonal antibody binding complement protein 5 (C5 receptor CD59), blocking complement upstream and reducing hemolysis. Case Summary In 1999 we diagnosed PNH in a male 54 year-old. Therapy with prednisone and blood transfusions started. After 13 years (2012) of continuative steroid, we started eculizumab every 14 days. Clinical and laboratory improvement has been reported, the prednisone therapy has been tapered; no further hemolytic crises reappeared. However, mild anemia, high reticulocytes count, high LDH serum levels are still reported. Actually, despite to suboptimal response, the patient shows a good quality of life. Conclusion Here we report a case of PNH with a fully documented medical history of long-term steroid therapy confirming efficacy and safety of eculizumab. However “C3 tick over” effect may induce suboptimal clinical results with residual hemolytic activity also on heavy steroid treated patients.

Key words: paroxysmal nocturnal hemoglobinuria, eculizumab, steroids, hemolysis