IgA nephritis associated with plasminogen abnormalities.

Two patients with IgA nephritis associated with hereditary plasminogen abnormalities are described. One patient had dysplasminogenemia and the other had plasminogen deficiency. In both patients, renal biopsy specimens showed significant arteriosclerotic changes in addition to mesangial proliferation. Increased fibrinopeptide A concentration in their plasma suggested increased thrombin generation. In one patient, no systemic arteriosclerosis coexisted, judging from normal optic fundi and the absence of neurological and cardiac abnormalities. In IgA nephritis, renal vascular hyalinosis is often observed, probably resulting from vascular injury. Thus, it was suggested that the decreased fibrinolysis and renal vascular injury of these patients synergistically induced more fibrin thrombi and accelerated arteriosclerosis of the kidney. These cases imply the important role of fibrinolytic disorders in the progression of IgA nephritis.