Simultaneous occurrence of diabetic glomerulosclerosis, IgA nephropathy, crescentic glomerulonephritis, and myeloperoxidase-antineutrophil cytoplasmic antibody seropositivity in a Chinese patient.

We report the case of a 72-year-old woman with a long-standing history of diabetes mellitus who presented with heavy proteinuria and rapid deterioration in renal function. She had a high titer of myeloperoxidase-antineutrophil cytoplasmic antibody (MPO-ANCA). The renal biopsy specimen revealed features of diabetic glomerulosclerosis, crescentic glomerulonephritis, and IgA nephropathy. Treatment with steroid and cyclophosphamide resulted in significant improvement in renal function and normalization of MPO-ANCA level. This case highlights the importance of having a high index of suspicion for coexisting glomerulonephritis in diabetic patients presenting with proteinuria. The clinical course of patients with diabetic glomerulosclerosis, IgA nephropathy, crescentic glomerulonephritis, and MPO-ANCA seropositivity seems to resemble that of ANCA-associated, rapidly progressive glomerulonephritis and is potentially amenable to aggressive immunosuppressive therapy.