Treatment of Hepatitis B Virus-Associated Nephropathy

Epidemiological studies have shown a relationship between hepatitis B virus (HBV) infection and development of proteinuria in some patients (most commonly children), with a predominance for male gender and histological findings of membranous nephropathy on renal biopsy. The presence of immune complexes in the kidney suggests an immune complex basis for the disease, but a direct relation between HBV and membranous nephropathy (or other types of glomerular diseases) remains to be proven. Clearance of HBV antigens, either spontaneous or following antiviral treatments results in improvement in proteinuria. Thus, prompt recognition and specific antiviral treatment are critical in managing patients with HBV and renal involvement. The present review focuses on treatment of HBV with special emphasis given to antiviral therapies, its complications, and dosing in patients with HBV-associated kidney disease. Copyright © 2011 S. Karger AG, Basel Published online: June 15, 2011 Fernando C. Fervenza, MD, PhD Division of Nephrology and Hypertension Mayo Clinic College of Medicine, 200 First Street, SW Rochester, MN 55901 (USA) Tel. +1 507 266 7083, E-Mail fervenza.fernando @ mayo.edu © 2011 S. Karger AG, Basel 1660–2110/11/1191–0041$38.00/0 Accessible online at: www.karger.com/nec D ow nl oa de d by : 54 .7 0. 40 .1 1 11 /5 /2 01 7 7: 11 :3 8 P M Elewa /Sandri /Kim /Fervenza Nephron Clin Pract 2011;119:c41–c49 c42 An example of the potential incidental findings can be given regarding IgA nephropathy. Lai et al. [11, 20, 21] examined the ability of HBV antigenemia in inducing IgA nephropathy in patients with IgA nephropathy with no previous history of liver diseases and normal liver function tests. All were HBsAg and anti-HBcAg positive with high titers. Immunoperoxidase studies using monospecific polyclonal antibodies revealed HBcAg and HBsAg in the nuclei and cytoplasm of glomerular mesangial cells in the majority of patients. The authors concluded that immune complexes involving HBcAg and HBsAg may induce IgA nephropathy in persons who carry HBV. It is, however, unclear whether IgA nephropathy is a ‘complication’ of HBV infection or merely a coincidental association in countries where both HBV and IgA nephropathy are common, e.g. China, where nationwide cross-sectional seroepidemiological study in the 1990s showed that approximately 60% of the population had a history of HBV infection, and 9.8% of persons were chronically infected with HBV [22] , and at the same time, IgA nephropathy is the most common form of a glomerular disease in this population [23] . The pathogenesis of HBV-associated nephropathy, including potential immunopathogenetic mechanisms, biosocial background and genetic factors has been the subject of a recent review [24] . The diagnosis of HBV-mediated glomerular disease requires detection of the virus in the blood and the exclusion of other causes of glomerular diseases.