What is paroxysmal nocturnal hemoglobinuria (PNH)?

By William Aird

An acquired hematologic disease resulting from loss-of-function variants in the PIGA gene, occurring in 1 or more hematopoietic stem cells, which eventually expand over normal hematopoiesis. As a result, all progeny blood cells lack surface glycosylphosphatidylinositol-linked proteins, including complement regulators, CD5919 and CD55. This leads to surface complement activation, initiation of the terminal complement pathway, membrane attack complex (MAC) assembly and intravascular hemolysis. Learn more here.