1-3 There is evidence that previous HBV infection, marked only by the presence of antibodies to HBV—notably hepatitis B core antibody

(anti-HBc) with or without hepatitis B surface antibody (anti-HBs)—may also indicate persistent buy RO4929097 HBV infection. Previous HBV infection has also been linked with progressive liver disease, particularly as a cofactor among patients with another form of underlying liver disease such as chronic hepatitis C or alcoholic liver disease. Prior studies have shown that the prevalence of occult HBV infection is higher in countries where HBV infection is prevalent, in patients with serological markers of previous HBV infection, and in patients who

have risk factors for HBV PARP inhibitor infection such as those with human immunodeficiency virus or hepatitis C virus (HCV) infection. What remains uncertain is the clinical significance of low-level, persistent HBV infection, especially among patients with another cause of liver disease. Several studies, mostly from Europe and Japan, have found a higher rate of occult HBV infection in patients with chronic HCV infection who have HCC compared with HCV-infected patients with no HCC.1-4 In some of these studies, the prevalence of occult HBV infection in HCV patients with HCC was as high as 60%-70%.2-4 However, data on the prevalence of occult HBV infection in HCV patients and the contribution of occult HBV to HCC in the United States are DOK2 limited. The Hepatitis C Antiviral Long-term Treatment against Cirrhosis (HALT-C) Trial prospectively followed patients with chronic HCV infection and advanced hepatic fibrosis for clinical outcomes including HCC. All

the patients tested negative for HBsAg in the serum at enrollment. This large cohort provides an excellent opportunity to study the clinical significance of previous or occult HBV infection in patients with chronic HCV infection in the United States. The aims of this analysis were to compare the prevalence of previous and occult HBV infection in HALT-C patients who developed HCC and those who did not develop HCC. In addition, we assessed the demographics, risk factors for HCV infection, and laboratory and histological indicators of liver disease in HALT-C patients with and without previous and occult HBV infection. AFP, alpha-fetoprotein; anti-HBc, hepatitis B core antibody; anti-HBs, hepatitis B surface antibody; CI, confidence interval; HALT-C, Hepatitis C Antiviral Long-term Treatment against Cirrhosis; HBsAg, hepatitis B surface antigen; HBV, hepatitis B virus; HCC, hepatocellular carcinoma; HCV, hepatitis C virus; OR, odds ratio; PCR, polymerase chain reaction. The design of the HALT-C Trial has been described.