Rapidly progressive glomerulonephritis concomitant with diabetic nephropathy

We describe a rare case of a rapidly progressive glomerulonephritis (RPGN) superimposed on diabetic nephropathy. A 68-year-old woman with non-insulin-dependent diabetes mellitus (NIDDM) complicated with diabetic triopathy demonstrated a rapid deterioration of renal function. Her urinary sediment contained many red blood cell (RBC) cells and casts, suggesting an additional renal disease accompanying diabetic nephropathy. Renal biopsy revealed crescent formation in many glomeruli characteristic of the pauci-immune type of RPGN. Steroid pulse therapy transiently halted the deterioration in renal function, but the patient died of pneumonia complicated with methicillin-resistant staphylococcus aureus (MRSA) infection. The unusual findings in diabetic nephropathy indicated the coexistence of primary glomerulonephritis and diabetic glomerulosclerosis in this case.