Timing and efficacy of doxycycline in macrolide-resistant Mycoplasma pneumoniae pneumonia in children: a single-center retrospective study

Background Outbreaks of macrolide-resistant Mycoplasma pneumoniae (MRMP) in children have posed ongoing treatment challenges. This study aimed to assess the efficacy of doxycycline in treating MRMPP at different time points, offering insights for public health strategies. Methods We retrospectively analyzed children with MRMPP hospitalized between September 2022 and February 2024. They were divided into three main groups based on antibiotic use: (1) those who received azithromycin only (AZI group); (2) those who received doxycycline only (DOX group); (3) those who received azithromycin followed by doxycycline (ATD group), divided into two subgroups according to the duration of azithromycin use: azithromycin use < = 3-day subgroup (ATD1) and azithromycin use > 3-day subgroup (ATD2). Oxygen therapy, electronic bronchoscopy, hormones and gamma globulin were also recorded. Length of hospital stay and duration of fever were used as outcome measures for comparative analyses. Propensity score matching (PSM) analysis was used to adjust the score. Results 312 eligible children were identified. The DOX group had the highest 48-h fever reduction rate (80%). The AZI group had a higher proportion of oxygen (77%) and e-bronchoscopy (75%) use, and the ADT group had a higher proportion of hormone use (39%). After adjustment for PSM, oxygen use remained higher in the ATD2 group than in the DOX+ATD1 group ( p = 0.026). Conclusions Early use of doxycycline in treating MRMPP reduces reliance on adjuvant therapies, thus easing the burden on healthcare resources.