Semi-quantitative real-time PCR: A useful approach to identify persons with low replicative chronic hepatitis B.

Antiviral therapy can be avoided during the low replicative phase of chronic Hepatitis B virus (HBV) infection which is characterized notably by HBV DNA concentration below 2000IU/ml. Simplified diagnostic tests can improve access to HBV DNA monitoring in resource-limited settings. The capacity of a new semi-quantitative real-time PCR approach based on sample-to-standard relative detection of the target to discriminate samples with HBV DNA levels above or below the clinical threshold of 2000IU/ml was compared to a quantitative assay (Roche CobasAmpliPrep/CobasTaqMan HBV Test v2.0). The semi-quantitative assay correctly identified 40/40 (100%) low replicative HBV DNA patients and 58/61 (95%) samples from HBV-infected subjects with moderate/high levels of viral DNA. Our results suggested that this alternative PCR test is efficient to guide therapeutic decision based on identification of low replicative HBV infection from all of the chronic hepatitis B carriers requiring treatment, and may be useful in resource-limited settings where the vast majority of cases live.