ABSTRACT
Hepatitis B vims [HBV] infection in patients who lack detectable hepatitis B surface antigen [HBsAg] is called occult hepatitis B infection. Such infections have been frequently identified in patients with chronic hepatitis C liver disease, but their prevalence is not known.207 patients with chronic hepatitis C who were HCV-RNA and anti-HCV positive were studied for HBV-DNA by PCR, and for HBsAg and anti-HBc by ELIS A. DNA was extracted by high pure nucleic acid kit [Roche-Germany]. HB V-DNA amplification was done with a set of primer directed to the pre-S region. HBsAg and anti-HBc were evaluated by a commercially available ELIS A kit [Dade Behring].23 of 207 patients with chronic hepatitis C liver disease [11.1%] were positive for HB V-DNA [co-infection]. Among this group 17 patients [8.2%] were HBsAg negative [occult infection]. 8 of 17 patients with occult infection [47%] were anti-HBc positive and 9 were anti-HBc negative [53%]. No significant difference was found in epidemiological and biochemical parameters in patients with HCV alone in comparison with HCV co-infected with occult hepatitis B [p= 0.453 for ALT and77= 0.498 for AST]. Occult hepatitis B virus infections occur frequently in patients with chronic hepatitis C liver disease and may have clinical significance