Rapidly evolving skin manifestations due to progressive thrombosis in a patient with paroxysmal nocturnal haemoglobinuria resolved with prompt initiation of eculizumab

Abstract

Funding sources: none. Conflicts of interests: P.M. has sat on advisory boards for Alexion. Dear Editor, Paroxysmal nocturnal haemoglobinuria (PNH) is a rare acquired clonal disorder of the haematopoietic stem cell. PNH arises from mutations in the PIGA gene, which encodes glycosylphosphatidylinositol (GPI)‐anchored proteins. Consequently, these mutations result in a deficiency of GPI‐anchored proteins in cell membranes.1 This deficiency causes PNH red blood cells to be susceptible to complement‐induced intravascular haemolysis.2 However, PNH is also characterized by a high rate of thrombosis.3 4 Venous and arterial thrombosis can be the first symptom of PNH. PNH‐induced thrombosis often occurs at unusual sites and may progress in days to weeks.5 Moreover, thromboembolic complications and consequences are the leading cause of morbidity and death in PNH.4 The pathogenesis of thrombosis in PNH is complex and not completely elucidated at this time.3 The clinical picture of PNH is highly variable and depends on the PNH clone size, factors of complement activation and whether or not there is an underlying bone marrow disease. Complications of PNH occur spontaneously or can be triggered by bacterial or viral infections, for example by highly contagious parvovirus B19.6 7 Cutaneous manifestations of PNH comprise rapidly evolving purpura, haemorrhagic bullae and ulcerations presumably due to necrosis, secondary to intravascular clotting.8 9 10