The role of P30 adhesin detected by ultrasensitive ELISA in the clinical diagnosis and management of Mycoplasma pneumoniae.

BACKGROUND

Mycoplasma pneumoniae (MP) is a common cause of pediatric respiratory infections, but its diagnosis remains challenging due to nonspecific clinical features and the limitations of conventional laboratory tests.

METHODS

We evaluated the diagnostic and clinical utility of P30 detection using the ultrasensitive TN-cyclon™ assay in 67 hospitalized children with respiratory tract infections. Diagnostic accuracy was compared with bacterial culture, respiratory PCR, and serum IgM testing. Associations between P30 levels and clinical course, laboratory findings, co-infection status, radiographic severity, and macrolide resistance were also analyzed.

RESULTS

P30 TN-cyclon™ showed strong diagnostic performance (sensitivity 83.33 %, specificity 92.31 %), outperforming serum IgM (sensitivity 48.08 %) while remaining slightly less sensitive than PCR (sensitivity 93.94 %) but comparable in overall diagnostic performance. ROC analysis yielded an AUC of 0.892, with an optimal cutoff of 0.4 pg/mL for MP infection. Patients with co-infections had lower mean P30 levels than those with mono-infection, though not statistically significant. P30 concentrations were not associated with radiographic severity. In macrolide-resistant cases, higher P30 levels were observed, with ROC analysis identifying 2.45 pg/mL as a potential threshold (AUC = 0.66).

CONCLUSIONS

P30 is a reliable biomarker for the rapid diagnosis of MP, with superior accuracy to serology and practical advantages over PCR in clinical settings. While its predictive value for macrolide resistance is modest, integration with other biomarkers may enhance its clinical utility. TN-cyclon™ offers a promising tool for timely management of MP infections in children.