DELAYED ERYTHROID AND PLATELET RESPONSE TO ECULIZUMAB IN PAROXYSMAL NOCTURNAL HAEMOGLOBINURIA – A CASE REPORT AND LITERATURE REVIEW

Abstract

Paroxysmal nocturnal haemoglobinuria (PNH) is an acquired clonal disorder of haemopoiesis characterised by haemolytic anaemia, thrombophilia and variable cytopaenias. Complement-mediated blood cell damage leads to the main clinical features of PNH, including anaemia, haemoglobinuria, other haemolysis-related symptoms, thrombosis, and thrombocytopaenia. The treatment of PNH has remained supportive until the development of the first complement inhibitor, eculizumab. This antibody efficiently blocks terminal complement activity, quickly halting intravascular haemolysis. However, both the time course and the magnitude of erythroid and platelet responses to this drug are highly variable. Here, we report a case illustrating both delayed erythroid and platelet responses to eculizumab, and review mechanisms and therapeutic options for partial responses.

Keywords

• paroxysmal nocturnal haemoglobinuria
• intravascular haemolysis
• anaemia
• thrombocytopaenia
• bone marrow failure
• eculizumab