Background
Hepatitis B virus (HBV) infection is diagnosed when the circulating HBV surface antigen (HBsAg) is serologically detected. Occult HBV infection is defined as the infection state negative for HBsAg serology, but it has shown viral genome persistence in infected individuals. The aim of the study is to determine the prevalence of occult HBV among patients with chronic hepatitis negative to HBsAg in the presence or absence of hepatitis C virus (HCV) infection.
Patients and methods
This study was conducted on a total number of 55 patients with chronic hepatitis (liver cirrhosis in 44 cases, nonalcoholic fatty liver in six cases) and hepatocellular carcinoma in five cases. All studied cases were subjected to routine liver function tests, HBsAg, HBsAb, hepatitis c virus immunoglobulin G (HbcIgG), α-fetoprotein, HCV RNA, and HBV DNA detection.
Result
All cases were negative to HBsAg and HBsAb in the presence or absence of HCV infection. HBV DNA detection by real-time RT-PCR confirmed the positivity of HBV infection [occult hepatitis b infection (OBI)] in two (4.5%) out of 44 cases of cirrhotic liver and represented 3.6% of the total cases studied with a viral DNA of 116 and 159 copies/ml, respectively. One case of OBI had a high level of α-fetoprotein (392 Iu/ml) and the second case had high copies of HCV RNA 127 000 copies/ml, that is coinfection. HbcIgG was positive in 31.8% in cirrhotic patients (including one out of the two positive OBI). HCV RNA was negative in 100.0% of nonalcoholic fatty liver, positive in 39 (one was positive OBI) cases with cirrhosis with a median value of 45 000 copies and in four out of the five hepatocellular carcinoma cases with a median value of 1.85E+08. This is statistically significant (P=0.01). We come to the conclusion that occult HBV do exist in our community. The diagnosis of OBI should be based on high sensitivity of HBsAg and HBV DNA testing.