Division of Microbiology, Department of Pathology and Laboratory Medicine, Queen Elizabeth II Health Sciences Centre;
Can J Infect Dis Med Microbiol. 2009 Winter;20(4):e157-62. doi: 10.1155/2009/493275.
In 2007, Atlantic Canada experienced a large outbreak of mumps predominately in university students who had received a single dose of measles, mumps and rubella vaccine. The present study describes the performance characteristics of reverse transcriptase polymerase chain reaction (RT-PCR) on buccal and urine specimens and immunoglobulin M (IgM) serology in this partially immune population.
Patients presenting with symptoms suspicious for mumps had a serum, urine and a buccal swab collected for diagnostic testing. Persons were classified as a 'confirmed' case according to the Public Health Agency of Canada's definition. Sera were tested using an enzyme-linked immunoassay. Detection of mumps virus in buccal swabs and urine samples was performed by RT-PCR.
A subset of 155 cases and 376 non-cases that had all three specimens submitted was used for calculating the performance characteristics. The sensitivity of RT-PCR on buccal swabs, urine specimens and IgM serology were 79%, 43% and 25%, respectively. The specificity of RT-PCR on buccal swabs, urine specimens and IgM serology was 99.5%, 100% and 99.7%, respectively. Only 12 of 134 (9%) patients had positive urine specimens in the presence of negative oral swabs.
RT-PCR on buccal swabs is the ideal specimen for diagnosis. Testing an additional urine sample in an outbreak setting did not increase the diagnostic yield significantly, but doubled testing volume and cost. In addition, the data suggest that, in this partially immune group, IgM serology has little value in the diagnosis of acute infection.
2007 年，大西洋省份爆发了一场主要发生在已接种一剂麻疹、腮腺炎和风疹疫苗的大学生中的腮腺炎疫情。本研究描述了在这群部分免疫人群中，逆转录聚合酶链反应（RT-PCR）对口腔和尿液标本以及免疫球蛋白 M（IgM）血清学的检测性能。
出现疑似腮腺炎症状的患者采集血清、尿液和口腔拭子进行诊断检测。根据加拿大公共卫生局的定义，将患者分类为“确诊”病例。血清采用酶联免疫吸附试验进行检测。通过 RT-PCR 检测口腔拭子和尿液样本中的腮腺炎病毒。
对 155 例确诊病例和 376 例非病例进行了分析，这两组病例均提交了所有三种标本。RT-PCR 对口腔拭子、尿液标本和 IgM 血清学的敏感性分别为 79%、43%和 25%。RT-PCR 对口腔拭子、尿液标本和 IgM 血清学的特异性分别为 99.5%、100%和 99.7%。在 134 例患者中，仅有 12 例（9%）在口腔拭子阴性的情况下尿液标本为阳性。
口腔拭子的 RT-PCR 是诊断的理想标本。在疫情爆发期间，额外检测尿液样本并不能显著提高诊断率，但会使检测量和成本翻倍。此外，数据表明，在这群部分免疫人群中，IgM 血清学在急性感染的诊断中几乎没有价值。
