A nephropathy presenting the microparticles in the glomerular basement membrane in a patient of hepatitis B viral infection.

We report here unique electron microscopy findings showing clusters of deposition of spherical and tubular microparticles in a glomerular basement membrane (GBM) of a 46-year-old Japanese male with membranous nephropathy. Another distinct feature was the deep infolding of podocyte membranes into the GBM. Light microscopy showed the ladder formation of the GBM suggesting membranous nephropathy, while the immunofluorescent examination was atypical for the absence of the global capillary deposition of IgG and C3. He had mild liver dysfunction with positive hepatitis B antigen. Antibodies to hepatitis B surface antigen reacted weakly on the GBM in the immunohistochemistry. We suspected the unique findings of this case might be related to the hepatitis B viral infection.