Visual detection of Mycoplasma pneumoniae by the recombinase polymerase amplification assay coupled with lateral flow dipstick.

Mycoplasma pneumoniae (Mp) is a common cause of respiratory infections in school-age children. In the present study, a recombinase polymerase amplification (RPA) assay combined with lateral flow dipstick (LFD) was developed for diagnosis of Mp. Specific primers and a probe were designed for the Mp p1 gene. The optimal reaction conditions of the RPA-LFD assay were 37 °C and 25 min. The minimal detection limit of the RPA assay was 10 DNA molecules. The RPA method had no cross-reaction with the other 14 common pathogens tested. The practicability of the assay for detecting Mp in clinical samples from the patients suspected to be Mp infection was also determined. The nucleic acids of the clinical samples were extracted by the DNA Rapid extraction reagent which took about 10 min. The clinical specimens were detected by the RPA method, and the result showed high agreement with that of the qPCR commercial kit. The RPA-LFD method with high sensitivity and specificity is easy to perform and is an alternative method for field detection in resources-limited settings.