De novo glomerulonephritis in renal allografts with hepatitis C virus infection.

The purpose of this study was to examine the influence of hepatitis C virus (HCV) infection on the occurrence of posttransplant de novo glomerulonephritis (GN). Of 165 patients selected for the study, 44 were HCV positive and 121 HCV negative. Light and immunofluorescence microscopy were performed on all biopsies and clinical and laboratory findings reviewed. Fifteen (34%) of the 44 HCV positive patients showed de novo GN (4 membranous, 11 membranoproliferative) at a mean of 47 +/- 22 months. But only 8 (6.6%) of 121 HCV negative patients showed de novo GN (5 anti-glomerular basement membrane nephritis in recipients with Alport's disease, 2 membranous GN, 1 membranoproliferative GN) at a mean of 60 +/- 39 months. The risk of development of de novo GN was higher among patients with HCV infection (P < .001). The presence of de novo GN in HCV positive patients impaired graft survival compared with HCV positive patients without de novo GN (P < .01). The incidence of recurrence of primary disease, mainly focal segmental glomerulosclerosis, membranous glomerulonephritis, membranoproliferative glomerulonephritis, and IgA nephropathy, was higher in HCV negative patients (29%) compared with HCV positive patients (6.8%; P = .001), namely, 50%, 57.6%, 25%, and 69%, respectively. In conclusion, HCV infection showed a strong influence on the development of de novo GN. For this reason, it is important to follow HCV positive recipients with a renal biopsy even when there are no significant clinical or laboratory findings.