Comparison of different detection methods for Mycoplasma pneumoniae infection in children with community-acquired pneumonia

Abstract Background: Due to the lack of a sensitive, specific and rapid detection method, etiological diagnosis of pneumonia caused by Mycoplasma pneumoniae ( M. pneumoniae, MP ) is a constantly challenging issue. This retrospective study aimed to compare the diagnostic methods for mycoplasma pneumoniae in children and evaluate their values. Methods: From November 2018 to June 2019, 830 children with community-acquired pneumonia were selected from the Department of Respiratory Medicine, Shanghai Children's Medical Center. On the first day of hospitalization, sputum, throat swabs, venous blood samples were collected for MP-IgM (particle agglutination, PA), MP-IgM (immune colloidal gold technique, GICT), MP-DNA, MP-RNA (simultaneous amplification and testing, SAT), and MP-DNA (real-time polymerase chain reaction, RT-PCR) Results: Among these 830 children, RT-PCR showed that the positive rate was 36.6% (304/830), in which the positive rate of macrolide-resistant (A2063G mutation) accounted for 86.2% (262/304). Using RT-PCR as the standard, MP-RNA (SAT) had the highest specificity (97.5%), and MP-IgM (PA) had the highest sensitivity (74.0%) and Youden index (53.7%). If MP-RNA (SAT) was combined with MP-IgM (PA), its Kappa value (0.602), sensitivity (84.2%), specificity (78.7%), Youden index (62.9%), were higher than those of single Mycoplasma pneumoniae detection. Conclusions: Our research indicated that a combination of MP-RNA (SAT) plus MP-IgM (PA) as an early diagnostic method for children with clinical manifestations of Mycoplasma pneumoniae pneumonia might lead to reliable results.