Doxycycline treatment for drug-resistant Mycoplasma pneumoniae pneumonia and evaluation of key predictive factors for refractory disease.

OBJECTIVE

Mycoplasma pneumoniae pneumonia (MPP) in children is a common respiratory infection, with rising concerns over macrolide-resistant strains. The aim of this study is to establish an effective diagnostic prediction model for refractory MPP (RMPP) and evaluate doxycycline as an alternative treatment for macrolide-unresponsive MPP (MUMPP).

METHODS

106 children with RMPP receiving doxycycline and 73 children with MUMPP treated with azithromycin were retrospectively analyzed. For all patients, the detection of MP-DNA in BALF, alongside clinical criteria, served to confirm active MP infection and infer phenotypic macrolide unresponsiveness/resistance. Univariate and multivariate logistic regression analyses were then used to identify clinically available risk factors for the development of RMPP among these patients with MP pneumonia.

RESULTS

The doxycycline group had significantly shorter fever duration, fewer lavage procedures, reduced steroid use, and shorter hospital stays compared to the azithromycin group (P < 0.05). Multivariate analysis identified four independent risk factors for RMPP: duration of macrolide use before admission, days of fever before hospitalization, procalcitonin (PCT), and C-reactive protein (CRP). A nomogram based on these factors showed excellent discrimination, with an AUC of 0.982 (95% CI: 0.961-1.000). The calibration curve approached the 45-degree line, and decision curve analysis (DCA) indicated that the nomogram provided positive net benefit across a reasonable range of threshold probabilities, supporting its potential clinical utility.

CONCLUSION

In children with MUMPP, doxycycline treatment is associated with superior clinical outcomes compared to azithromycin. A nomogram incorporating readily available clinical factors can effectively identify patients at risk of developing RMPP, supporting early intervention.