Development of a fast and low-cost qPCR assay for diagnosis of acute gas pharyngitis

作者：Kolukirik Mustafa^*; Yilmaz Mesut; Ince Orhan; Ketre Canan; Tosun Ayse Istanbullu; Ince Bahar K

来源：Annals of Clinical Microbiology and Antimicrobials, 2016, 15(1): 46.

DOI：10.1186/s12941-016-0162-0

• Group A streptococci
• Acute pharyngitis
• qPCR
• Rapid antigen detection test

Background: Group A streptococci (GAS) are the most common bacterial cause of acute pharyngitis and account for 15-30 % of cases of acute pharyngitis in children and 5-10 % of cases in adults. In this study, a real-time quantitative PCR (qPCR) based GAS detection assay in pharyngeal swab specimens was developed.
Methods: The qPCR assay was compared with the gold standard bacterial culture and a rapid antigen detection test (RADT) to evaluate its clinical performance in 687 patients. The analytical sensitivity of the assay was 240 cfu/swab. Forty-five different potential cross-reacting organisms did not react with the test. Four different laboratories for the reproducibility studies were in 100 % (60/60) agreement for the contrived GAS positive and negative swab samples.
Results: The relative sensitivities of the RADT and the qPCR test were 55.9 and 100 %; and the relative specificities were 100 and 96.3 %, respectively. Duration of the total assay for 24 samples including pre-analytical processing and analysis changed between 42 and 55 min depending on the type of qPCR instrument used. A simple DNA extraction method and a low qPCR volume made the developed assay an economical alternative for the GAS detection.
Conclusion: We showed that the developed qPCR test is rapid, cheap, sensitive and specific and therefore can be used to replace both antigen detection and culture for diagnosis of acute GAS pharyngitis.

• 出版日期2016-8-8