Viral nephropathy.

Viral infections can cause many glomerular diseases. The diagnostic criteria for virus-related nephropathy include detailed clinical and laboratory data, and tissue molecular analysis. Several mechanisms are involved in the pathogenesis of virus-related nephropathy, including tropism of the virus in the kidney, induction of abnormal immune complexes, direct cytopathogenic effects, and multiorgan failure. Hepatitis B virus is associated with membranous nephropathy and mesangiocapillary glomerulonephritis in endemic areas. Hepatitis C virus causes various forms of glomerulonephritis, including cryoglobulinemia-mediated glomerulonephritis. Infection with HIV is associated with a collapsing focal segmental glomerulosclerosis, a distinctive disease that affects mainly Africans and African Americans. In the course of HIV infection, other types of immune complex glomerulonephritis can occur, most frequently in whites. Recent reports indicate a role for parvovirus B19 in 'idiopathic' collapsing focal segmental glomerulosclerosis. Both hantaviruses, and coronaviruses associated with severe acute respiratory syndrome, can lead to acute renal failure. Renal biopsy followed by appropriate serological and molecular testing is essential for defining virus-related glomerular lesions and guiding prognostic and therapeutic evaluation.