Urinary fibrin-fibrinogen degradation products and intraglomerular fibrin-fibrinogen deposition in various renal diseases

Abstract

The typing of the urinary fibrin-fibrinogen degradation products (FDP) and the deposition of fibrin-fibrinogen, factor XIII-subunit A (XIII-A) and factor XIII-subunit S (XIII-S) in the glomeruli were investigated in the children with several kinds of renal diseases. In acute glomerulonephritis with diffuse proliferative lesion, the urinary FDP were composed of fragments X,Y,D and E. There was no D-dimer fragment detected in the urine, although, mild deposition of fibrin-fibrinogen, XIII-A and XIII-S in the glomeruli was observed. The urinary FDP may be derived from plasma fibrinogen or serum FDP. In nephrotic syndrome with diffuse proliferative or focal global sclerosing lesion and in purpura nephritis with mesangial proliferation with crescents, the urinary FDP consisted of fragments X and Y, and lacked in D-dimer. In these cases, the major part of fibrin-fibrinogen in the glomeruli might be fibrinogen or non-cross-linked fibrin, and FDP excretion might arise from glomerular permeability or from lysis of fibrinogen or non-cross-linked fibrin. In one patient with hemolytic uremic syndrome and in another patient with systemic lupus erythematodes nephropathy, intense deposition of fibrin-fibrinogen, XIII-A and XIII-S within the glomerular capillaries or mesangial area were observed. In the urine of those cases, D-dimer was detected, which seems to reflect the lysis of cross-linked fibrin in the glomeruli.