Immunohistochemical detection of the terminal C5b-9 complement complex in children with glomerular diseases.

Kidney biopsies were obtained in 28 children with glomerular diseases and studied using indirect immunofluorescence and immunoperoxidase for IgG, IgA, IgM, C1q, C3c, C4, fibrinogen and the neoantigens of the terminal C5b-9 complement complex. C5b-9 deposits were detected in glomeruli of 14, in tubules of eight and in vessels of 12 cases. Patients with C5b-9 deposits fared worse than those without such deposits, even with the same histopathological type of glomerulonephritis. The C5b-9 complex suggests an in situ complement activation.