C3 and paroxysmal nocturnal hemoglobinuria: Unlike PNH, C3G represents a highly heterogeneous spectrum of conditions that may be due to genetic abnormalities in various complement components (such as C3-, factor B-, factor H-, factor I-, and factor H-related proteins), the development of autoantibodies against complement components, or nephritic factors that stabilize C3 and/or C5 convertases [33].