儿童与成人慢性乙型肝炎患者的临床特征差异明显。乙型肝炎病毒(Hepatitis B virus,HBV)病毒准种特征与其致病特性紧密相连,HBV病毒Core基因区富含免疫表位,该区域的准种特征直接反映病毒变异与病毒应对宿主免疫压力间的动态过程。文章...儿童与成人慢性乙型肝炎患者的临床特征差异明显。乙型肝炎病毒(Hepatitis B virus,HBV)病毒准种特征与其致病特性紧密相连,HBV病毒Core基因区富含免疫表位,该区域的准种特征直接反映病毒变异与病毒应对宿主免疫压力间的动态过程。文章通过扩增170名儿童慢性乙型肝炎患者及121名成人慢性乙型肝炎患者病毒Core基因区,按照病毒基因型以及病毒e抗原(Hepatitis B virus e antigen,HBe Ag)状态进行分组,使用序列复杂度、多样性、非同义突变率(Non-synonymous substitution ratio,d N)、同义突变率(Synonymous substitution ratios,d S)等指标衡量不同组别之间的病毒准种特征;使用不同模型计算不同组别中受到正选择压力的位点,进一步结合HBV Core基因区免疫表位信息,进行正选择位点的定位分析。结果发现,儿童乙型肝炎病毒患者体内病毒Core基因区序列复杂性和多样性低于成人患者,且前者Core基因区正选择位点个数显著低于后者,这说明儿童慢性乙型肝炎患者体内病毒受到的选择压力低于成人患者。在儿童及成人慢性感染病人组中,HBe Ag阳性病人体内病毒受到的选择压力低于HBe Ag阴性病人。儿童及成人慢性感染患者体内病毒存在13个正选择位点,大多数正选择位点位于已知的抗原表位上。本研究从分子进化角度揭示了儿童与成人慢性乙型肝炎病例体内病毒Core基因区序列准种差异,为两类病人显著不同的临床表征提供了群体遗传学的解释。展开更多
AIM: To present the characteristics and the course of a series of anti- hepatitis B virus core antibody (HBc) antibody positive patients, who experienced hepatitis B virus (HBV) reactivation after immunosuppression. M...AIM: To present the characteristics and the course of a series of anti- hepatitis B virus core antibody (HBc) antibody positive patients, who experienced hepatitis B virus (HBV) reactivation after immunosuppression. METHODS: We retrospectively evaluated in our tertiary centers the medical records of hepatitis B virus surface antigen (HBsAg) negative patients who suffered from HBV reactivation after chemotherapy or immunosuppression during a 3-year period (2009-2011). Accordingly, the clinical, laboratory and virological characteristics of 10 anti-HBc (+) anti-HBs (-)/HBsAg (-) and 4 anti-HBc (+)/antiHBs (+)/HBsAg (-) patients, who developed HBV reactivation after the initiation of chemotherapy or immunosuppressive treatment were analyzed. Quantitative determination of HBV DNA during reactivation was performed in all cases by a quantitative real time polymerase chain reaction kit (COBAS Taqman HBV Test; cut-off of detection: 6 IU/mL). RESULTS: Twelve out of 14 patients were males; median age 74.5 years. In 71.4% of them the primary diagnosis was hematologic malignancy; 78.6% had received rituximab (R) as part of the immunosuppressive regimen. The median time from last chemotherapy schedule till HBV reactivation for 10 out of 11 patients who received R was 3 (range 2-17) mo. Three patients (21.4%) deteriorated, manifesting ascites and hepatic encephalopathy and 2 (14.3%) of them died due to liver failure. CONCLUSION: HBsAg-negative anti-HBc antibody positive patients can develop HBV reactivation even 2 years after stopping immunosuppression, whereas prompt antiviral treatment on diagnosis of reactivation can be lifesaving.展开更多
文摘AIM: To present the characteristics and the course of a series of anti- hepatitis B virus core antibody (HBc) antibody positive patients, who experienced hepatitis B virus (HBV) reactivation after immunosuppression. METHODS: We retrospectively evaluated in our tertiary centers the medical records of hepatitis B virus surface antigen (HBsAg) negative patients who suffered from HBV reactivation after chemotherapy or immunosuppression during a 3-year period (2009-2011). Accordingly, the clinical, laboratory and virological characteristics of 10 anti-HBc (+) anti-HBs (-)/HBsAg (-) and 4 anti-HBc (+)/antiHBs (+)/HBsAg (-) patients, who developed HBV reactivation after the initiation of chemotherapy or immunosuppressive treatment were analyzed. Quantitative determination of HBV DNA during reactivation was performed in all cases by a quantitative real time polymerase chain reaction kit (COBAS Taqman HBV Test; cut-off of detection: 6 IU/mL). RESULTS: Twelve out of 14 patients were males; median age 74.5 years. In 71.4% of them the primary diagnosis was hematologic malignancy; 78.6% had received rituximab (R) as part of the immunosuppressive regimen. The median time from last chemotherapy schedule till HBV reactivation for 10 out of 11 patients who received R was 3 (range 2-17) mo. Three patients (21.4%) deteriorated, manifesting ascites and hepatic encephalopathy and 2 (14.3%) of them died due to liver failure. CONCLUSION: HBsAg-negative anti-HBc antibody positive patients can develop HBV reactivation even 2 years after stopping immunosuppression, whereas prompt antiviral treatment on diagnosis of reactivation can be lifesaving.
