All of the following conditions are associated with PNH, EXCEPT:

PNH is not usually associated with a massive splenomegaly. Complications of paroxysmal nocturnal hemoglobinuria includes thrombosis (mesentric, cerebral or hepatic vein), infection secondary to neutropenia, hemorrhage secondary to thrombocytopenia. It can also evolve into aplastic anemia, and rarely into acute myeloid leukemia. Thrombosis is one of the most immediately life-threatening complications of PNH which could be due to deficiency of CD59 on the PNH platelet causing inappropriate platelet activation. Ref: Harrison's Internal Medicine, 18th Edition, Chapter 106