[Very low-level viremia: new clinical attention-requiring problem during the course of anti-hepatitis B virus treatment].

Clinical studies have validated low-level viremia is associated with a variety of adverse outcomes in patients with chronic hepatitis B during the course of receiving nucleos(t)ide analogue antiviral therapy. With the advancement of PCR technology, the high sensitivity PCR detection of HBV DNA can reach the lower limit of detection of < 5-10 IU/mL. The standard criterion for judging among patients who have achieved complete virological response is HBV DNA levels < 20 IU/ml. The use of highly sensitive PCR tests can detect very low-level viremia (HBV DNA < 20 IU/ml, but > 5-10 IU/mL) in some patients. However, there are currently fewer relevant studies, and more research data needs to be accumulated to answer this clinical question of whether long-term very low-level viremia affects the clinical outcome of patients with chronic hepatitis B.