百日咳疑似病例实验室检测法的比较研究

Comparison of laboratory detection methods of suspected pertussis cases

目的对2019年河南省监测医院的百日咳疑似病例进行实时荧光聚合酶链式反应(real-time polymerase chain reaction,real-time PCR)和定量ELISA实验室检测比较。方法4家监测医院采集百日咳疑似病例的鼻咽拭子和血清,通过real-time PCR检测百日咳鲍特菌(Bordetella Pertussis)特异性核酸片段和定量ELISA检测百日咳毒素抗体(anti-pertussis toxin IgG,PT-IgG)。结果对446例百日咳疑似病例实验室共检测出126例阳性病例,阳性率为28.25%。阳性和阴性病例的发病天数差异有统计学意义(P<0.05)。各年龄组百日咳阳性率差异有统计学意义(P<0.05);各年龄组的发病天数差异有统计学意义(P<0.05)。鼻咽拭子real-time PCR检出百日咳鲍特菌核酸阳性76例,阳性率为17.04%,阳性和阴性病例的发病天数差异有统计学意义(P<0.05)。各年龄组间阳性率差异有统计学意义(P<0.05)。ELISA检测PT-IgG抗体浓度,检出阳性74例,阳性率为16.59%,发病天数差异无统计学意义(P>0.05)。各年龄组ELISA检测阳性率的差异有统计学意义(P<0.05)。发病>22~29 d时检测阳性率最高,为39.06%,不同发病天数检测阳性率差异有统计学意义(P<0.05)。发病1~15 d内real-time PCR检测阳性率最高,为25.58%,不同发病天数real-time PCR检测阳性率差异有统计学意义(P<0.05)。>22~29 d ELISA检测阳性率最高,为25.00%,不同发病天数ELISA检测阳性率差异无统计学意义(P>0.05)。>22~29 d时,同时2种方法检测阳性率最高,为9.38%。2种检测方法结果均为阳性的一致率为5.38%。结论real-time PCR和ELISA检测均适用于实验室百日咳疑似病例检测且有很好的互补性,建议可将二者同时应用于百日咳的实验室检测。

Objective To monitor hospital’s suspected cases of pertussis for laboratory testing and to compare the performance of two detection methods,real-time polymerase chain reaction(real-time PCR)and enzyme-linked immunosorbent assay(ELISA).Methods Nasopharyngeal swabs and sera of suspected cases of pertussis were collected from four surveillance hospitals in Henan Province in 2019.Real-time PCR was used to detect DNA of Bordetella pertussis,and ELISA was used to quantitatively detect anti-pertussis toxin IgG(PT-IgG).Results A total of 126 positive cases were detected in 446 suspected cases of pertussis,with an overall positive rate of 28.25%.Among them,76 cases were detected by real-time PCR,with a positive rate of 17.04%;there was significant difference in onset days between positive and negative cases(P<0.05),as well as the positive rates among different age groups(P<0.05).74 cases were detected by ELISA,with a positive rate of 16.59%;and the difference in the positive rate among different age groups was significant(P<0.05).The overall positive rate was the highest in days 22;to 29;after onset,accounting for 39.06%,with significant difference in onset days(P<0.05).Real-time PCR had the highest positive rate when the duration of illness was less than 15 days,accounting for 25.58%;while the positive rate of ELISA reached peak at the period of 22 to 29 days,with a positive rate of 25.00%.There was significant difference in onset days of positive cases detected by real-time PCR(P<0.05),but not by ELISA.Simultaneous detection of positive cases by the two methods got the highest positive rate during onset period of 22 to 29 days,accounting for 9.38%.The consistent rate of positive cases detected by the two methods was 5.38%.Conclusion Both real-time PCR and PT-IgG ELISA are suggested to apply for laboratory diagnosis of suspected pertussis cases simultaneously with its good applicability and complementarity to each other.