Type I membranoproliferative glomerulonephritis in a renal allograft: A recurrence induced by a cytomegalovirus infection?

A 40-year-old white woman with end-stage renal disease from idiopathic type I membranoproliferative glomerulonephritis (MPGN) developed proteinuria and renal dysfunction 7 weeks after cadaveric donor renal transplantation. At the same time, a primary cytomegalovirus (CMV) infection was diagnosed. Complement levels were low, A renal biopsy disclosed an acute exudative proliferative glomerulonephritis with influx of polymorphonuclear granulocytes (PMNs), with granular deposits of C3, C1q, IgG, and IgM. The immunofluorescence (IF) and electron microscopy (EM) findings were compatible with an early stage of a type I MPGN. CMV could not be detected in the glomeruli nor elsewhere in the kidney by IF or EM. The patient was treated with ganciclovir. In a renal biopsy 3 weeks later, the exudative lesions had disappeared, and some glomeruli now showed the characteristic lesions of a type I MPGN with an increase of mesangial cells and matrix, and reduplication of the glomerular basement membrane. Over the following period, repeated biopsies were performed. The activity of the glomerular inflammation and immune complex deposits paralleled the waxing and waning of the CMV viral load. After 10.5 months, the graft was removed because of a life-threatening systemic fungal infection. At that time, the CMV infection had cleared, and in the transplantectomy material, the membranoproliferative pattern of injury had disappeared, and in the glomeruli hardly any deposits were found. These data strongly suggest that a primary CMV virus infection can induce an apparent recurrence of type I MPGN. (C) 2000 by the National Kidney Foundation, Inc.