Evaluation of a multiplex PCR assay for detection of respiratory viruses and Mycoplasma pneumoniae in oropharyngeal swab samples from outpatients

Zhang, Ying; Cao, Lan; Xu, Zhi; Zhu, Pingting; Huang, Bing; Li, Kuibiao; Xu, Yang; Zhang, Zhoubin; Wu, Yong; Di, Biao

Multiplex PCR-based NAATs have been increasingly used for syndromic diagnosis, due to their high throughput, high sensitivity, high specificity, cost-effectiveness, and great clinical significance. [10] [11] [12] The ResP assay is based on multiplex PCR amplification and capillary electrophoretic separation of PCR amplicons by length. This technique has been used for pathogen detection and subtype classification of pediatric acute lymphoblastic leukemia. 13, 14 By comparing the results with a standard size marker of targeted pathogens, pathogens in samples can be separated and identified as expected. 15 The subtypes of most viruses were not designed to be further distinguished by this assay, except for influenza virus A. The influenza virus A pdmH1N1 (2009) and H3N2 are the two subtypes which are most popular in China recently. Therefore, a patient whose specimen is positive for influenza virus A but negative for influenza virus A pdmH1N1 (2009) or H3N2 is probably infected by an uncommon influenza virus A, such as H7N9, H5N1, H5N6 avian influenza virus A [16] [17] [18] and has to be immediately quarantined once it is confirmed. It should be noted that F I G U R E 2 A negative result from the multiple PCR assay ResP. X-axis represents the sizes of amplification products and Y-axis represents the signal strength. huRNA, human RNA; huDNA, human DNA; IC, internal control Further investigation is needed to evaluate the performance of ResP on these pathogens.