From the Centers for Disease Control and Prevention, National Center for Immunization and Respiratory Diseases, Division of Bacterial Diseases, Meningitis and Vaccine Preventable Diseases Branch, Atlanta, GA.
Pediatr Infect Dis J. 2013 Sep;32(9):942-5. doi: 10.1097/INF.0b013e3182947ef8.
United States national surveillance data show that the use of culture for pertussis diagnostics has sharply declined, whereas polymerase chain reaction (PCR) is now the most common testing method. PCR testing for pertussis is rapid and sensitive, but the lack of standardization and variable specificity is concerning.
A web-based survey containing 12 questions was sent to public health, commercial and hospital-based US laboratories performing clinical diagnostics to determine the pertussis diagnostics used. An extensive real-time PCR (RT-PCR) questionnaire accompanied a proficiency panel assessing the types of extraction methods, RT-PCR methods and current quality control in place at the laboratories. The proficiency panel of 12 specimens containing Bordetella pertussis at various concentrations and negative controls was created to detect cross-contamination and assess the lower limit of detection.
One hundred twenty-three (35%) of 355 respondents from the web-based survey performed diagnostic tests for the presence of B. pertussis. Eighty-three (71%) labs reported performing culture, whereas 67 (54%) labs used PCR. All 41 laboratories that consented to participate in the proficiency exercise used the IS481 RT-PCR target; however, a variety of extraction and RT-PCR methods were employed. The laboratories correctly identified 92% of the B. pertussis specimens, and 5% of the laboratories (1.8% of the panel specimens) reported at least 1 false-positive.
The small percentage of false-positives suggests that adequate procedures are in place to prevent cross-contamination. Differing extraction and PCR methods as well as variable analytic sensitivity emphasize the necessity for an external well-defined quality control program and interlaboratory pertussis PCR harmonization.
美国国家监测数据显示，用于百日咳诊断的培养法的使用急剧下降，而聚合酶链反应（PCR）现在是最常见的检测方法。PCR 检测百日咳快速且灵敏，但缺乏标准化和可变特异性令人担忧。
我们向从事临床诊断的美国公共卫生、商业和医院实验室的人员发送了一份包含 12 个问题的网络调查，以确定使用的百日咳诊断方法。一份内容广泛的实时 PCR（RT-PCR）问卷附有一个能力验证小组，评估实验室采用的提取方法、RT-PCR 方法和当前的质量控制情况。创建了包含不同浓度百日咳博德特氏菌和阴性对照的 12 个样本能力验证小组，以检测交叉污染并评估最低检测限。
我们从网络调查中收到了 123 个（35%）回复者的 123 个（35%）回复，其中 83 个（71%）实验室报告进行了培养，67 个（54%）实验室使用了 PCR。所有同意参加能力验证的 41 个实验室都使用了 IS481 RT-PCR 靶标，但采用了多种提取和 RT-PCR 方法。实验室正确识别了 92%的百日咳博德特氏菌样本，5%的实验室（占小组样本的 1.8%）报告了至少 1 个假阳性。
少量的假阳性表明采取了充分的程序来防止交叉污染。不同的提取和 PCR 方法以及可变的分析灵敏度强调了需要有一个外部明确的质量控制方案和实验室间百日咳 PCR 协调。
