Fibrinogen Catabolism In The Nephrotic Syndrome

Children with a nephrotic syndrome with renal biopsy findings of either minimal change disease (MCD) or focal glomerulosclerosis (FGS) had been followed serially by plasma fibrinogen chromatographic and other blood coagulation and plasma fibrinolytic assays. Patients with MCD were studied during: 1) relapse without steroid treatment (n=34); 2) relapse on steroid treatment (n=12); 3) early remission on steroid treatment (n=14); 4) late remission on steroids (n=17); and 5) late remission no steroids (n=10). The control group comprised 50 aged matched healthy children. Untreated MCD patients, regardless of disease etiology, showed statistically significant increases in plasma fibrinogen, plasma high molecular weight fibrin(ogen) complexes (average 79 mg/dl compared to 24 ml/dl control) (p < 0.001), in fibrinogen first derivative concentration and α₂-macroglobulin, but factor XIII, α₁-antitrypsin, plasminogen and antithrombin III concentrations were within the normal range. These findings document pathologically enhanced intravascular fibrin deposition, presumably occurring locally in the glomerulus and with enhanced fibrino- genolysis. Laboratory values reverted toward normal with steroid therapy and were normal in patients in remission whether or not remission was steroid-induced. Patients in relapse showed laboratory findings similar to those of the untreated patient. Laboratory findings in FGS patients in clinical relapse paralleled those found in untreated MCD patients, with disease remission laboratory findings also reverted to normal. It has recently been suggested (J. Ped. Neph. 1:18, 1980) that long-term anticoagulant therapy in FGS patients might prove effective in prevention of glomerulosclerosis and chronic renal failure. Our findings would strengthen the rationale for this therapeutic approach.