Cutaneous Thrombosis in Paroxysmal Nocturnal Haemoglobinuria: A Rare Manifestation of a Common Complication

Paroxysmal nocturnal haemoglobinuria (PNH) is a rare clonal disorder of haematopoietic stem cells characterized by complement-mediated intravascular haemolysis and a high risk of thrombosis and bone marrow failure. While venous thrombosis in atypical sites such as intra-abdominal and cerebral veins is well documented, cutaneous thrombosis remains an exceptionally rare manifestation. We report a case of a 72-year-old female with PNH who presented with acute haemolysis and subsequently developed painful, erythematous skin lesions with central necrosis. Skin biopsy confirmed cutaneous thrombosis. Due to the unavailability of complement inhibitors, she was treated with therapeutic low molecular weight heparin followed by long-term anticoagulation with apixaban. The lesions resolved without progression, and she remained thrombosis-free over a three-year follow-up despite ongoing haemolysis requiring transfusions.
This case highlights the importance of considering cutaneous thrombosis in PNH patients presenting with rapidly evolving skin lesions. Early diagnosis and prompt anticoagulation are critical. Although complement inhibitors have revolutionized PNH management, their limited accessibility in low-resource settings necessitates reliance on anticoagulation. Literature reveals varied approaches to managing cutaneous thrombosis, emphasizing individualized care. This report underscores the need for clinical vigilance and tailored treatment strategies in resource-constrained environments.