Glomerular injury associated with hepatitis C infection: a correlation with blood and tissue HCV-PCR.

Membranoproliferative glomerulonephritis, with or without cryoglobulinemia, and membranous glomerulonephritis are the best characterized glomerulonephropathies associated with hepatitis C virus (HCV) infection. Other more unusual patterns of glomerular injury, including IgA nephropathy, focal segmental glomerulosclerosis, crescentic glomerulonephritis, fibrillary glomerulonephritis, immunotactoid glomerulopathy, and thrombotic microangiopathy, have also been associated with HCV infection, but primarily on an anecdotal basis. It remains uncertain whether the patterns of glomerular injury seen in HCV infected patients, particularly the unusual patterns, represent a disease process specifically related to HCV infection or whether they represent nonspecific patterns of injury due to other causes that happen to occur in HCV-infected patients. We examine this issue by reviewing the epidemiological and pathological evidence in the literature that either supports or refutes a specific relationship between HCV and the pattern of glomerular injury. We also include our experience with 31 HCV-infected patients. In addition, the pathogenesis of HCV-associated glomerulonephropathies is discussed with an emphasis on the significance of detecting HCV in renal biopsies by reverse transcriptase-polymerase chain reaction.