2023 Volume 72 Issue 1 Pages 68-76
Mycoplasma pneumoniae pneumonia is one of the most common community-acquired pneumonias and accounts for 10–20% of the pneumonia cases among children. The precise and timely detection of M. pneumoniae is critical because delayed diagnosis will cause disease exacerbation and prolonged treatment partly because of the development of macrolide resistance. We compared the bacteria detection ability of Smart Gene®, a fully automated genetic analyzer based on the QP method, with that of the conventional QP method used in our laboratory. M. pneumoniae culture strains of known concentrations were used and 104 patients with suspected mycoplasma pneumonia were recruited in this study. ①M. pneumoniae culture strains were serially diluted with physiological saline and analyzed by both methods and the minimum detection limits were compared between these two methods. The minimum detection sensitivities were almost the same for both methods. ②We compared the detection ability and the presence of resistance mutations using pharyngeal swabs. Both methods showed good agreement in terms of sensitivity, specificity, and match rate of detection and resistance mutation. ③When cryopreserved M. pneumoniae DNA specimens extracted from residual specimens after analysis using the mycoplasma antigen rapid diagnostic kit were used, the sensitivity, specificity, and match rate of Smart Gene® were 75.9%, 100.0%, and 87.3%, respectively. The results of both methods were consistent for the presence of resistance mutations. Smart Gene® can detect M. pneumoniae infection and the presence of macrolide-resistant mutations in a short time, and it is considered to be a highly useful test method in mycoplasma treatment because it can contribute to the early diagnosis and appropriate use of antimicrobial agents.
