RESUMO
It is believed that immune complexes play a role in the development of renal pathology in preeclampsia. To ensure this, 10 cases with residual proteinuria were biopsied 2-4 weeks postpartum. The biopsies were studied by light microscopy and tested for immunofluorescence [IF]. Light microscopy revealed the occurrence of endotheliosis, together with axial mesangial cellular proliferation with or without increase of matrix and one specimen showed focal segmental sclerosis. In addition, tubular degeneration [7 cases] and interstitial lymphocytic infiltration [2 cases] were noticed. IF showed positive granular subendothelial and mesangial deposits of IgM [9 cases], IgG [6 cases], C3 [5 cases] and fibrin [7 cases]. Renal biopsies of 2 cases with postpartum hemorrhage leading to acute renal failure, revealed endotheliosis but showed no deposits by IF. The placentae of 8 of the cases and 8 normal primigravida labors were tested for deposits by IF and revealed the occurrence of fibrin deposits and negligible immunoglobulins in most of the specimens and C3 and C4 deposits in 4 of the preeclampsia cases. These findings suggested an important pathogenic role of immune complexes in renal involvement in preeclampsia