输血传播病毒(TTV)重叠感染在慢性乙型肝炎病毒感染患者中的临床意义

目的：研究乙型肝炎病毒感染患者TTV重叠感染情况及初步探讨TTV的致病性。方法：在ORF1区设计特异性引物建立巢式多聚酶链式反应（PCR），检测乙型肝炎病毒感染患者血清中TTV DNA，对PCR产物进行分子克隆和测序。结果：献血员、慢性乙型肝炎病毒携带者、慢性乙型肝炎和慢性重型乙型肝炎患者TTV DNA阳性率分别为10％、11％、27％、48％。其中前两者与后两者比较均有显著差异，慢性乙型肝炎和慢性重型乙型肝炎患者相比也有显著差异（P＜0．05），乙型肝炎病毒感染者中其HBV感染复制指标的阳性率在TTV DNA阳性与TTV DNA阴性组之间无明显差异（P＞0．05）。慢性乙型肝炎和慢性重型乙型肝炎患者的ALT和TBIL在TTV DNA阳性病人组与TTV DNA阴性病人组之间比较有显著性差异（P＜0．05），TTV DNA阳性病人组明显高于TTV DNA阴性病人组。结论：献血员中存在TTV感染，乙型肝炎病毒感染患者重叠感染TTV较常见。慢性乙型肝炎和慢性重型乙型肝炎患者TTV DNA阳性率明显高于献血员和慢性乙型肝炎病毒携带者的阳性带，提示TTV的重叠感染可能是HBV感染病情加重因素之一，TTV重叠感染对HBV的复制可能不存在相互作用。

Clinical Significance of the Infection of Transfusion Transmitted Virus in the Patients with Hepatitis B

Objective:The rate of transfusion transmitted virus (TTV) infection in the patients with hepatitis B and its clinical significance was investigated.Methods:A nested polymerase chain reaction (nested-PCR) assay with specific primers from open reading frame one (ORF1) of TTV genome was established to detect TTV DNA in the serum sample from the patients with hepatitis B; The PCR product was cloned and sequenced. Results:TTV DNA was detected in the serum from 4 of 40 (10%)blood donors, 7 of 64 (11%)chronic HBV carriers, 39 of 140(27%)chronic hepatitis B patients, and 76 of 160 (48%) chronic severe hepatitis B patients. The frequence of TTV DNA positivity is doubled in chronic hepatitis B patients and four times more in chronic severe hepatitis B patients than that of chronic HBV carriers and blood donors candidates, it is also significantly higher in chronic severe hepatitis B patients than that of chronic hepatitis B patients ( P <0.05).The HBV replication markers positive rate is not significantly different between patients with TTV superinfecion or not ( P >0.05) .The level of ALT and TBIL in chronic hepatitis B and chronic severe hepatitis B patients is significantly higher in the patients with TTV than those without TTV ( P <0.05).Conclusions: The results of the study suggest that TTV infection is common in the patients with hepatitis B. The TTV superinfecion in chronic hepatitis patients may be one of causes to be responsible for their clinical exacerbation. The superinfection of TTV maybe do not interfere HBV replication.