Andres L. Brodsky, Laura B. Colin
Hospital de Clinicas ‘Jose de San Martin’, Hematology Division, Department of Medicine, University of Buenos Aires, Argentina
Disclosure: No potential conflict of interest.
Citation: EMJ Hema. 2013;1:20-24.
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.