Background: Hepatitis C virus (HCV) is a major cause of acute and chronic hepatitis throughout the world. Several extrahepatic manifestations, including glomerulonephritis, have been reported to be associated with this type of infection. Cryoglobulinaemic and non-cryoglobulinaemic membranoproliferative glomerulonephritis (MPGN) and membranous nephropathy (MN) are the commonest lesions associated with HCV. Results of treatment of these patients with interferon therapy have been disappointing, since relapse of the viraemia and subsequent relapse of the renal disease are major problems. Combination of interferon with ribavirin in patients with chronic liver disease has been shown to increase the rate of sustained response.
Methods: In this work, 20 patients with HCV-associated glomerulopathy were subjected to an in-depth evaluation of their kidney lesions and HCV involvement. Laboratory, histopathological, immunohistochemical, and electron-microscopy techniques were used. The patients received interferon therapy for 12 months; in interferon-resistant subjects, interferon was combined with ribavirin.
Results: MPGN was the commonest kidney lesion, being reported in 85% of these cases, followed by MN and mesangioproliferative glomerulonephritis (10 and 5% respectively). Mixed cryoglobulinaemia was encountered in 60% of the cases. Twelve months' anti-viral treatment resulted in aviraemia in 25% of cases, while liver enzymes were normalized in 75%, 24-h proteinuria significantly decreased (from median 4 g to 1.10 g, P=0.001), serum albumin increased (from median 2.50 to 3.55 g/dl, P=0.012), lower viral titres (from median 1.15 to 0.53 mega-Eq/ml, P=0.049), and C3 and C4 concentrations returned to normal. Basal serum creatinine and viral titres were important determinants of response to treatment.
Conclusion: This study supports the relationship between HCV and glomerulonephritis, especially MPGN, and the use of a combination of interferon and ribavirin in the treatment of selected cases of HCV-related glomerulopathy.