Abstract:

Objective

To analyze the epidemiological changes and clinical characteristics of severe Mycoplasma pneumoniae pneumonia （MPP） in children，and to explore potential factors influencing the rising trend of M.pneumoniae （MP） infections post-2023，providing insights for optimizing treatment strategies.

Methods

A retrospective review of clinical data from children hospitalized with MPP between January 2018 and May 2024 was conducted.Demographic，epidemiological，and clinical features were analyzed，along with differences in imaging，laboratory findings，and treatment between mild and severe cases.

Results

Post-2023，the positive rate of MP-IgM detection significantly increased，reaching 10.61% in 2023 and 18.12% from January to May 2024.Hospitalized MPP cases accounted for 11.16% to 13.73%.The median age of the observed group was 6 years，with higher incidences of fever （86.38%），high fever （47.84%），and antipyretic use （84.39%） compared to the control group （median age 3 years，62.20%，24.39%，and 53.65%，respectively； P＜0.05）.Imaging revealed that the observed group had more cases with multi-lobe involvement（47.84%），high-density lesions （66.45%），and lung consolidation （28.57%） compared to the control group（9.76%，25.00%，and 6.01%，respectively； P＜0.005）.The observed group also had higher CRP （14.62±18.45 mg/L），PCT （0.16±0.38 ng/ml），steroid use （71.10%），and tetracycline use （23.26%） compared to the control group （9.82±13.38 mg/L，0.10±0.14ng/ml，38.41%，and 18.30%，respectively）.Hospital stay duration did not differ，but the observed group had more chest X-ray re-examinations （39.05%） and delayed inflammation resolution （32.23%） compared to the control group （20.73% and 15.24%，respectively； P＜0.001）.

Conclusion

Post-2023，MP infections in children have shown a trend towards severity，characterized by older age，high fever，multi-lobe involvement，and elevated inflammatory markers.Early lung imaging combined with MP nucleic acid and drug resistance gene testing is valuable for identifying severe MPP.The rational use of tetracyclines and steroids should be guided by resistance monitoring and individualized analysis.

Key words: Mycoplasma pneumoniae, Pneumonia, Children, Clinical characteristics