Exploring Clinical Characteristics and Risk Factors of Mycoplasma pneumoniae-Induced Segmental/Lobar Pneumonia in Chongqing, China, During 2023: A Single-Center Retrospective Cohort Study of Hospitalized Children.

Purpose: Mycoplasma pneumoniae (MP)-segmental/lobar pneumonia represents a growing proportion of Mycoplasma pneumoniae pneumonia (MPP) in children. We aimed to identify the clinical characteristics and risk factors for MP-segmental/lobar pneumonia in children to facilitate early diagnosis and intervention. Methods: We conducted a retrospective cohort study at a tertiary pediatric center in Chongqing, China, involving 1406 children hospitalized for MPP from January to December 2023. Based on imaging findings, patients were categorized into MP-ordinary pneumonia group and MP-segmental/lobar pneumonia group. Clinical data were compared, and univariate and multivariate logistic regression analyses were performed to identify independent risk factors. The predictive performance was assessed using receiver operating characteristic (ROC) curves. Results: The MP-segmental/lobar pneumonia group exhibited a significantly longer duration of pre-admission fever, longer hospital stays, and higher rates of bronchoscopy, respiratory failure, and pulmonary complications. (all P < 0.05). Logistic regression analysis identified the following independent risk factors for MP-segmental/lobar pneumonia: sex, days with fever prior to admission, C-reactive protein (CRP), D-dimer, lactate dehydrogenase (LDH), platelet-lymphocyte ratio (PLR), and platelet (PLT). ROC curve analysis identified five primary predictive indicators (days with fever prior to admission >5.5 days, D-dimer >0.539mg/L, CRP >11.33mg/L, LDH >309.5U/L, PLR >155.815) and two secondary predictive indicators (PLT >340.5×109/L, female sex) based on predicted efficacy. The combined use of these seven indicators further enhanced predictive performance (AUC = 0.741, 95% CI: 0.715-0.766). Conclusion: MP-segmental/lobar pneumonia exhibits more pronounced clinical symptoms and elevated inflammatory markers. The seven clinical indicators-days with fever prior to admission, CRP, D-dimer, LDH, PLR, PLT and female sex-serve as useful predictive markers for segmental/lobar pneumonia caused by MP. These indicators aid clinicians in the early diagnosis and intervention of MPP, thereby preventing its progression to segmental/lobar pneumonia.