Prediction Model for Severe Mycoplasma pneumoniae Pneumonia and Analysis of Macrolide-resistance in Children: A case-control Study

Background To analyze the clinical features, laboratory findings, and imaging characteristics of severe Mycoplasma pneumoniae pneumonia (SMPP) in children, identify early warning indicators, and characterize macrolide-resistant M. pneumoniae pneumonia (MRMPP). Additionally, we developed and validated a nomogram model for predicting the risk of SMPP. Methods This retrospective cohort study included children diagnosed with M. pneumoniae pneumonia (MPP) who were admitted to the West China Second Hospital of Sichuan University between September 2022 and February 2024. Data on demographics, clinical manifestations, laboratory results, and imaging findings were collected and analyzed. Results Compared to non-severe cases, children with SMPP had a significantly longer fever duration (8 days vs. 4 days, P < 0.001), higher peak body temperature (39.3°C vs. 38.5°C, P < 0.001), and a higher incidence of wheezing (13% vs. 0%, P < 0.05). There was no significant difference in macrolide resistance rates between the groups (P > 0.05). Radiological analysis revealed a higher frequency of pulmonary consolidation (69% vs. 0%, P < 0.001) and pleural effusion (22% vs. 7%, P = 0.031) in the SMPP cohort. LASSO regression identified eight key predictors: fever duration, peak body temperature, wheezing, extrapulmonary complications, hemoglobin levels, pulmonary consolidation, mosaic sign, and bronchial occlusion. The nomogram demonstrated excellent discriminative ability, with training and validation AUC values of 0.972 (95% CI 0.960–0.984) and 0.975 (95% CI 0.958–0.992), respectively. Conclusions We developed and validated a nomogram for quantitative risk assessment of SMPP. This model can aid clinicians in the early identification of severe cases and in optimizing treatment strategies.