—J. Charles Jennette, MD, describes a 25-year-old man with membranous nephropathy in whom dependence on isophane insulin suspension for diabetes mellitus developed after receiving high-dosage steroid therapy for an indefinite period. The linking of these two disorders with a common cause, though an intriguing thought, currently lacks substantiation.
Bernes et al,1 in 1962, observed positive immunofluorescence in diabetic kidneys using antiserum to beef insulin and suggested that the renal damage in diabetic patients might be caused by immune complex deposition, with insulin being the exogenous antigen. However, subsequent immunohistological studies by Westberg et al2 and Thompsen3 failed to confirm the immunologic cause of diabetic glomerulosclerosis. They concluded that the linear deposition of immunoglobulins along the glomerular and tubular basement membranes of diabetic kidneys is caused by nonspecific trapping of a variety of plasma proteins, including albumin and ceruloplasmin. Thus, the consensus of opinion at the moment is