Mode
Text Size
Log in / Sign up

Macrolide-resistant Mycoplasma pneumoniae prevalence at 94% in pediatric CAP cohortResistant pneumonia keeps kids sicker for days

AI-generated summary of the cited source, checked by automated accuracy review. How we work

Key Takeaway
Consider that macrolide-resistant M. pneumoniae is highly prevalent and linked to worse clinical outcomes in this pediatric cohort.

This retrospective cohort study included 71 pediatric patients with confirmed Mycoplasma pneumoniae community-acquired pneumonia in Anhui, China. The study compared macrolide-resistant M. pneumoniae (MRMP) infection to macrolide-susceptible M. pneumoniae (MSMP) infection.

The prevalence of macrolide resistance was 67 of 71 isolates (94.4%). The predominant molecular mechanism was the A2063G mutation, found in 81.7% of resistant isolates. MIC50/MIC90 for erythromycin was 126/512 μg/mL, and for azithromycin was 16/126 μg/mL.

Clinical outcomes were worse with MRMP. Median fever duration was 6.5 days for MRMP vs 4.0 days for MSMP. Median hospitalization duration was 7.0 days for MRMP vs 5.0 days for MSMP. Median hs-CRP was 11.2 mg/L for MRMP vs 4.8 mg/L for MSMP. Median LDH was 258.5 U/L for MRMP vs 210.3 U/L for MSMP. Treatment failure or antibiotic switch rates were 20.9% for MRMP vs 0% for MSMP. MRMP was associated with more persistent cough and delayed radiographic resolution.

Safety and tolerability were not reported. Key limitations include an extremely small comparator group (n=4 MSMP), the descriptive nature of the analysis, and the retrospective design. The practice relevance is that MRMP prevalence exceeded 94% in this cohort, and MRMP infections were associated with a prolonged clinical course and elevated inflammatory markers. Associations are reported, not causal, due to the observational design.

When kids catch pneumonia from Mycoplasma, doctors often reach for macrolide antibiotics like azithromycin. But in one hospital in Anhui, China, almost every case fought back. Researchers tested 71 children with confirmed Mycoplasma pneumonia and found that 67 of them—94%—had strains that resisted these drugs.

These resistant infections clearly took a heavier toll. Kids with resistant pneumonia had fever for about six and a half days, compared with four days for those with susceptible strains. Hospital stays were longer, too, and inflammatory markers were higher. Nearly 21% of resistant cases needed a different antibiotic because the first one didn’t work, while none of the susceptible cases did. Persistent cough and slower clearing on chest X-rays were also more common with resistant bugs.

This was a small look back at hospital records, with only four children whose infections were still susceptible to macrolides. That makes it hard to draw broad conclusions. Still, the pattern is stark: when the bacteria resist the usual medicine, kids are sicker for longer and more often need a change in treatment.

What this means for you:
Resistant Mycoplasma pneumonia means longer fevers and hospital stays for kids.

Study Details

Study typeCohort
EvidenceLevel 3
PublishedApr 2026
View Original Abstract ↓
IntroductionMacrolide-resistant Mycoplasma pneumoniae (MRMP) has reached extremely high prevalence among children in Asia. However, genotype -phenotype correlations and their impact on clinical outcomes in pediatric community-acquired pneumonia (CAP) remain insufficiently characterized in many regions of China. This study aimed to determine the prevalence, molecular mechanisms, antimicrobial susceptibility, and clinical characteristics of macrolide resistance in children with M. pneumoniae CAP in Anhui, China.MethodsA retrospective cohort study was conducted among 71 pediatric patients with confirmed M. pneumoniae CAP between October 2023 and September 2024. Macrolide resistance was assessed using 23S rRNA domain V sequencing and broth microdilution minimum inhibitory concentration (MIC) testing. Clinical features, laboratory markers, treatment response, and outcomes were descriptively compared between macrolide-resistant M. pneumoniae (MRMP) and macrolide-susceptible M. pneumoniae (MSMP) cases.ResultsOf the 71 isolates, 67 (94.4%) were macrolide-resistant, predominantly harboring the A2063G mutation (81.7%). The MIC₅₀/MIC₉₀ values for erythromycin and azithromycin were 126/512 μg/mL and 16/126 μg/mL, respectively. Compared with the small MSMP group (n = 4), children with MRMP appeared to have longer median fever duration (6.5 vs. 4.0 days), longer hospitalization (7.0 vs. 5.0 days), higher hs-CRP (11.2 vs. 4.8 mg/L), higher LDH (258.5 vs. 210.3 U/L), more persistent cough, delayed radiographic resolution, and higher treatment-failure or antibiotic-switch rates (20.9% vs. 0%).DiscussionMacrolide resistance exceeded 94% and was mainly driven by the A2063G mutation, accompanied by high MIC values. MRMP infections were associated with prolonged clinical course and elevated inflammatory markers; however, these findings should be interpreted cautiously due to the extremely small comparator group and the descriptive nature of the analysis.
Free Newsletter

Clinical research that matters. Delivered to your inbox.

Join thousands of clinicians and researchers. No spam, unsubscribe anytime.