全血EBV DNA载量检测在儿童EB病毒感染中的应用价值

目的：评价全血EBV DNA载量检测在儿童EB病毒（EBV）感染中的应用价值。方法将231例EBV活动感染儿童（原发感染174例，复发感染57例）、258例非活动EBV感染儿童（EBV既往感染）、45例无EBV感染健康儿童采用自动核酸提取实时荧光定量PCR法检测全血EBV DNA载量，探讨其与EBV感染的关系。结果 EBV活动性感染组全血EBV DNA阳性率81.8%，全血EBV DNA载量为（3.99±0.96）lg Copies/ml。EBV原发感染组与复发感染组的全血EBV DNA阳性率差异无统计学意义（字2＝0.419，P=0.517），EBV DNA载量差异无统计学意义（t=1.236，P=0.221）。非活动EBV感染儿童组全血EBV DNA阳性率10.9%，全血EBV DNA载量为（2.89±0.20）lg Copies/ml。EBV活动性感染组与非活动性感染组的全血EBV DNA阳性率差异有统计学意义（字2＝251.600，P=0.0001），全血EBV DNA载量差异有统计学意义（t=3.389，P=0.001）。非EBV感染组全血EBV DNA阳性率0。EBV原发感染组中，全血EBV DNA阳性率（82.7%）高于EBV- CA IgM阳性率（75.8%），差异有统计学意义（字2＝6.160，P=0.008），两者结果一致性不佳（Kappa=0.687）。以全血EBV DNA载量检测阳性作为诊断依据，敏感度75.9%，特异度91.2%，诊断符合率84.4%；在全血E-BV DNA载量为3.00lgCopies/ml时，是判断儿童EBV活动性感染的最佳临界点，敏感度70.1%，特异度95.3%，诊断符合率83.4%。结论全血EBV DNA载量是监测EBV活动性感染的独立指标，在儿童EBV感染诊断、疗效观察和愈后评估中的具有重要意义。

Detection of whole blood EBV DNA load in children with EB virus infection

Objective To evaluate the detection of whole blood Epstein- Barr virus （EBV） DNA load in childhood EBV in-fection. Methods Two hundred and thirty- one children with active EBV infection （174 cases with primary infection and 57 cases with recurrent infection）, 258 children with previous EBV infection and 45 healthy children were enrol ed in the study. Whole blood EBV DNA load was detected with automatic nucleic acid extraction method and real- time PCR. The relationship between EBV DNA load and EBV infection was analyzed. Results The positive rate of whole blood EBV in children with active EBV infection was 81.8%and the EBV DNA load was 3.99±0.96lg copies/ml. There were no significant differences between primary infection and recurrent infection groups （x2=0.419, P=0.517 and t=1.236, P=0.221, respectively）. The positive rate and whole blood EBV DNA load in children with inactive EBV infection were 10.9%and 2.89±0.20lg copies/ml respectively;there were significant dif-ferences between active and inactive patients（x2=251.6, P=0.0001 and t=3.389, P=0.001, respectively） . The positive rate of whole blood EBV DNA in healthy children was 0%. The positive rate of whole blood EBV DNA in primary EBV infection group was 82.7%, which was higher than that of EBV- CA IgM positive rate （75.8%, P=0.008 ） with a poor consistency （Kappa=0.687）. The sensi-tivity, specificity and accuracy of positive blood EBV DNA for diagnosis of EBV infection were 81.8%, 89.5%and 85.9%, respec-tively. Taking DNA load of 3.00lg copies/ml as cut- off value the sensitivity, specificity and accuracy for diagnosis of active EBV infection were 70.1%, 95.3%and 83.4%, respectively. Conclusion Detection of whole blood EBV DNA load can be used for di-agnosis and prognosis of EB virus infection in children.