Background: The influence of hepatitis C virus (HCV) treatment on the course of HCV cryoglobulinemic membranoproliferative glomerulonephritis (MPGN) is controversial.
Methods: Twenty-five patients with nephrotic-range proteinuria, mixed cryoglobulinemia, MPGN proved by renal biopsy, and HCV infection were studied for their response to antiviral treatment.
Results: After first-line treatment with prednisone, furosemide, or plasmapheresis, antiviral therapy with standard or pegylated interferon alfa and ribavirin was introduced in 18 patients. These patients were compared with 7 patients who did not receive antiviral treatment. Mean duration of antiviral treatment was 18 +/- 10 months, with a follow-up of at least 6 months after treatment withdrawal. HCV RNA clearance (sustained virological response) was achieved in 12 of 18 patients. Compared with values before antiviral therapy, a decrease in proteinuria was observed in sustained virological responders at the end of combination therapy, as well as at the end of follow-up (mean, 2.85 +/- 2.2 [SD] versus 1 +/- 1.4 and 0.4 +/- 0.8 g/d, respectively; P < 0.05). In sustained virological responders, cryoglobulin levels at the end of treatment (0.29 +/- 0.4 g/L) and end of follow-up (0.25 +/- 0.4 g/L) were decreased (P < 0.05) compared with pretreatment values (1.38 +/- 2.2 g/L). Conversely, no changes in serum cryoglobulinemia levels were observed in nonresponders or controls. Serum creatinine levels remained stable in the 18 patients with antiviral therapy, regardless of response to treatment.
Conclusion: Anti-HCV treatment improved HCV-associated cryoglobulinemic glomerulonephritis.