%0 Journal Article
%T Occult Hepatitis B: Clinical Viewpoint and Management
%A Mehdi Zobeiri
%J Hepatitis Research and Treatment
%D 2013
%I Hindawi Publishing Corporation
%R 10.1155/2013/259148
%X Occult HBV infection (OBI) is defined as HBV DNA detection in serum or in the liver by sensitive diagnostic tests in HBsAg-negative patients with or without serologic markers of previous viral exposure. OBI seems to be higher among subjects at high risk for HBV infection and with liver disease. OBI can be both a source of virus contamination in blood and organ donations and the reservoir for full blown hepatitis after reactivation. HBV reactivation depends on viral and host factors but these associations have not been analyzed thoroughly. In OBI, it would be best to prevent HBV reactivation which inhibits the development of hepatitis and subsequent mortality. In diverse cases with insufficient data to recommend routine prophylaxis, early identification of virologic reactivation is essential to start antiviral therapy. For retrieving articles regarding OBI, various databases, including OVID, PubMed, Scopus, and ScienceDirect, were used. 1. Introduction Hepatitis B virus (HBV) infection is a major global health problem with about 350¨C400 million chronically infected individuals [1]. HBV infection can induce a wide spectrum of clinical features, ranging from an inactive carrier state to fulminate hepatitis, cirrhosis, or hepatocellular carcinoma [2]. According to European Association for the Study of the Liver (EASL), about one-third of the world¡¯s populations have serological evidence of past or present HBV infection [3]. Many of these individuals may unknowingly carry the virus for several years after recovery from acute hepatitis B without showing any clinical or biochemical evidence of liver disease, and serological markers can identify different clinical states of viral persistence [4, 5]. HBV infection is usually diagnosed when circulating hepatitis B surface antigen (HBsAg) is detected. Chronic infection is characterized by persistence of this antigen and presence of HBV DNA in serum and resolved HBV infection when patients show seropositivity for ¨CHBc and HBs antibodies. Occult hepatitis B infection (OBI) is defined as the existence of low-level HBV DNA in the serum (<200£¿IU/mL), cells of the lymphatic (immune) system, and/or hepatic tissue in patients with serological markers of previous infection (anti-HBc and/or anti-HBs positive) and the absence of serum HBsAg. More than 20 percent of patients had no serologic markers because the antibody titer may become undetectable over time, leaving HBV DNA as the only marker of the infection. Thus depending on the HBV antibodies (anti-HBc and/or anti-HBs), OBI may be seropositive or seronegative [2, 3]. 2.
%U http://www.hindawi.com/journals/heprt/2013/259148/