Immune complex-mediated glomerulonephritis and interstitial pneumonia simulating Goodpasture's syndrome

An autopsy case of what was clinically considered to be Goodpasture's syndrome was investigated. The lung had hemorrhagic interstitial pneumonia, showing granular patterns of IgG and C3 along the alveoli by the immunofluorescent method and electron-dense subepithelial deposits by electron microscopy. The kidney had crescentic and segmental necrotizing glomerulonephritis associated with membranous nephropathy. Uneven, continuous patterns of immunofluorescent IgG and C3 along the GBM were noted. Electron microscopy showed numerous subepithelial deposits, and immunoelectron microscopy revealed that IgG was not present in the GBM itself but present in the subepithelial deposits. Anti-GBM antibody activity was not detected in the serum or the kidney eluate. It was suggested that renal and pulmonary lesions occurred through the same mechanism and in association with immune deposits. We propose that there is a disease having immune complex-mediated deposits. We propose that there is a disease having immune complex-mediated renal and pulmonary lesions which clinically resembles the conventional Goodpasture's syndrome.