What is a common cause of death in patients with paroxysmal nocturnal hemoglobinuria?

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare hematological condition characterized by the destruction of red blood cells due to complement-mediated lysis. One of the most significant complications associated with PNH is thrombosis, which tends to occur in unusual veins and can lead to serious complications such as deep vein thrombosis (DVT) or pulmonary embolism (PE). The underlying cause of thrombosis in PNH is related to the hypercoagulable state that results from the deficiency of certain proteins that normally help regulate the complement system and manage clotting.

Patients with PNH have an increased risk of developing thrombotic events due to the released hemoglobin and associated inflammatory factors, which promote clot formation. These thrombotic events can significantly impact mortality rates, making thrombosis a common cause of death in this population.

While acute infections, acute leukemia, and organ failure can also occur in patients with PNH, they are not as directly associated with mortality as thromboembolic events. The hypercoagulability seen in PNH is a hallmark of the condition, making thrombosis the most relevant and common cause of death among these patients.