Viral Nephropathies

Viral infections are important causative agents in renal disease and are responsible for significant morbidity and mortality. The diagnostic criteria for virus-related nephropathy include detailed clinical and laboratory data and tissue molecular analysis. Possible pathogenetic mechanisms include kidney tropism of the virus, 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. HIV infection is associated with a collapsing focal segmental glomerulosclerosis, a distinctive disease that mainly affects Africans and African Americans. In the course of HIV infection, other types of immune complex glomerulonephritis may occur. Recent reports indicate a role for parvovirus B19 in idiopathic collapsing focal segmental glomerulosclerosis. Acute kidney injury occurs in hantavirus and coronavirus-associated severe acute respiratory syndrome. Of particular interest are those viral infections with productive replication in the kidney, which often occur in immunocompromised hosts, such as renal allograft recipients. Epstein-Barr virus, cytomegalovirus, adenovirus, and BK polyomavirus are prominent members of this group causing specific diseases. Renal biopsy followed by appropriate serologic and molecular testing is essential for defining virus-related nephropathies and guiding prognostic and therapeutic evaluation. This review contains 4 figures, 3 tables, and 90 references. Key words: BK polyomavirus, cytomegalovirus, glomerulonephritis, hepatitis B, hepatitis C, HIV-associated nephropathy, viral infection