实时荧光定量聚合酶链式反应检测百日咳鲍特菌的效能研究

Real-time Polymerase Chain Reaction on Diagnosis of Bordetella Pertussis

背景百白破疫苗效价不足事件引发公众对百日咳的关注,但目前各种百日咳实验室检测方法均具有一定的局限性,无法满足快速进行病原学诊断的临床需求。目的评价一种商品化的实时荧光定量聚合酶链式反应(Q-PCR)试剂盒对百日咳鲍特菌(BP)感染的临床检测效果。方法2016年11月-2017年4月在首都医科大学附属北京儿童医院采集无热咳嗽患儿鼻咽拭子302例,以及临床诊断为百日咳患儿鼻咽拭子50例。采用Q-PCR与细菌培养方法筛查302例无热咳嗽患儿是否存在BP感染,并比较两种方法检测50例临床诊断百日咳病例的阳性率,综合评估Q-PCR的临床应用价值。结果302例无热咳嗽患儿中,以细菌培养为金标准时,Q-PCR检测的灵敏度为78.6%(11/14),特异度为95.8%(276/288),阳性预测值为47.8%(11/23),阴性预测值为98.9%(276/279)。在50例临床诊断百日咳病例的鼻咽拭子标本中,Q-PCR检测的阳性率为34.0%(17/50),细菌培养的阳性率为22.0%(11/50),两者比较,差异无统计学意义(χ^2=3.125,P=0.077)。结论以细菌培养结果为金标准,Q-PCR筛查百日咳的灵敏度及特异度较高;在为临床诊断百日咳患儿提供病原学证据中,Q-PCR与细菌培养方法检测阳性率相当。

Background The event caused by insufficient potency of pertussis vaccine drawed great public concern.Owing to the limitations of pertussis laboratory test,it is hard to meet the clinical needs of rapid etiological diagnosis.Objective To evaluate the effect of a commercialized quantitative polymerase chain reaction(Q-PCR)kit on diagnosis of infections caused by bordetella pertussis(BP).Methods A total of 302 nasopharyngeal swabs of children with cough but no heat and 50 nasopharyngeal swabs of children clinically diagnosed with pertussis were collected in Beijing Children's Hospital ,Capital Medical University from November 2016 to April 2017.Q-PCR and classical bacterial culture method were used to detect whether 302 children with cough but no heat were infected by BP as well as the corresponding.Positive rates of BP in 50 clinically diagnosed cases by two methods were compared to comprehensively evaluate the clinical value of Q-PCR.Results Compared with culture method,the sensitivity of Q-PCR in 302 cases was 78.6%(11/14),the specificity 95.8%(276/288),the positive predictive value 47.8%(11/23),and the negative predictive value 98.9%(276/279).The positive rate detected by Q-PCR was 34.0%(17/50) and that by bacterial culture was 22.0%(11/50).There was no significant difference between the two methods(χ^2=3.125,P=0.077).Conclusion Compared with culture method,the Q-PCR detection method achieved a higher sensitivity and specificity.Two methods had a similar positive rate in providing etiological diagnosis for patients clinically diagnosed with pertussis.