慢性乙型肝炎患者低病毒血症的研究现状及挑战

Current research and challenges of low-level viremia in patients with chronic hepatitis B

虽然新生儿普遍接种慢性乙型肝炎病毒(hepatitis B virus,HBV)疫苗,HBV的感染率开始大幅下降,但2016年我国慢性HBV感染者仍有8600万例。2019年,全球有2.96亿例慢性HBV感染者,且每年约有82万人死于HBV感染所致的肝衰竭、肝硬化或肝细胞癌(hepatocellular carcinoma,HCC)等相关疾病。多数慢性乙型肝炎患者经恩替卡韦、替诺福韦、丙酚替诺福韦等规范抗病毒治疗后,可以取得抑制病毒复制、延缓疾病进展的疗效。但随着人们对疾病更深层次的认识及检测技术的提升,临床发现部分患者经规范治疗48周后,血清HBV DNA低于2000 IU/mL,但持续或间歇地高于检测下限,即为低病毒血症状态。低病毒血症的发生机制目前尚不明确。相关研究已经表明,HBV低病毒血症影响患者的临床预后,主要表现为促进肝脏炎症、肝纤维化的进展及发生肝硬化失代偿、肝细胞癌、耐药的风险升高。对于HBV低病毒血症患者的治疗方案也尚未有明确建议。本文将对HBV低病毒血症的定义、可能的发生机制、临床意义及临床管理策略等方面进行介绍,为临床医师提供参考。

Although newborns are generally vaccinated against chronic hepatitis B virus,incidence of HBV infection decreases.However,in 2016,there were still 86 million cases of chronic HBV infection in China.In 2019,there were 296 million cases of chronic HBV infection worldwide,and approximately 820000 people die from related diseases caused by HBV infection annually,such as liver failure,cirrhosis or HCC.Mostly,the clinical treatment of patients with chronic hepatitis B can achieve therapeutic effects of inhibiting virus replication and delaying disease progression after standar-dized antiviral treatments(such as entecavir,tenofovir,and propofol tenofovir).But with a deeper understanding of the disease and the improvement of detection technology,it has been found in clinical practice that some patients,after 48 weeks of standardized treatment,had serum HBV DNA levels below 2000 IU/mL and continuously or intermittently exceeding the lower limit of detection,which indicates a state of low-level viremia(LLV).The mechanism of LLV is currently unclear.Related studies have shown that LLV of HBV affects the clinical prognosis of patients,mainly manifesting as promoting liver inflammation,development of liver fibrosis,and an increased risk of decompensated cirrhosis,hepatocellular carcinoma,and drug resistance.In addition,there are no clear recommendations for the treatment of patients with HBV LLV.This article will review the definition,possible mechanisms,clinical significance,and clinical management strategies of HBV LLV,providing reference for clinical physicians.