PATHOGENIC SIGNIFICANCE OF INTERLEUKIN-6 IN A PATIENT WITH ANTIGLOMERULAR BASEMENT-MEMBRANE ANTIBODY-INDUCED GLOMERULONEPHRITIS WITH MULTINUCLEATED GIANT-CELLS

We report a patient with anti-glomerular basement membrane disease who developed renal failure associated with systemic manifestations, incl uding acute-phase inflammatory reactions and plasmacytosis, Renal tiss ue obtained by an open surgical biopsy showed circumferential cellular crescents, multinucleated giant cells, and exudation of fibrin in all glomeruli, Immunofluorescence microscopy demonstrated deposition of i mmunoglobulin G, C3, and membrane attack complex along glomerular capi llary walls. Multinucleated giant cells were suggested to be macrophag e-monocyte lineage because they were CD68 positive, Bone marrow aspira tion showed an increase of plasma cells. Immunostaining showed intensi ve expression of interleukin-6 (IL-6) in practically every part of the renal sites involving multinucleated cells, crescents, tubules, and i nfiltrating cells, suggesting that one of the sources of systemically elevated IL-6 was the kidney. Serum IL-6, anti-glomerular basement mem brane antibody, and acute-phase proteins were markedly elevated, and r eturned dramatically to the normal level after corticosteroid therapy and plasmapheresis. We believe that IL-6 played an important role in t he development of many symptoms in the present case. (C) 1995 by the N ational Kidney Foundation, Inc.