Hepatitis C virus and its renal manifestations: a review and update.

Hepatitis C virus (HCV) causes chronic systemic infection, primarily affecting the liver. Although HCV mainly causes hepatitis, a significant portion of chronic HCV patients manifests with at least 1 extrahepatic involvement during the course of their illness. Chronic HCV infection can cause various types of renal diseases. The most common renal manifestations of HCV infection are essential mixed cryoglobulinemia leading to membranoproliferative glomerulonephritis (MPGN), MPGN without cryoglobulinemia, and membranous glomerulonephritis. On the other hand, patients with end-stage kidney disease are at an increased risk of acquiring HCV due to their frequent exposure to potentially contaminated devices in dialysis units and their long-term use of vascular access. Among dialysis patients or patients undergoing renal transplantation, the presence of HCV is associated with higher rates of mortality. The optimal antiviral therapy in patients with severe renal insufficiency is not yet well established and, in most cases, is associated with serious adverse effects. Randomized controlled trials looking at treatment options are lacking. This article reviews the pathophysiology of renal manifestations of chronic HCV infection, discusses recent insights into diagnostic and treatment options for HCV-induced glomerulopathies and HCV-infected dialysis patients, and describes the work-up of HCV-positive renal transplant candidates.