Construction of a nomogram combining CT and serum markers for predicting macrolide resistance gene mutation status in pediatric Mycoplasma pneumoniae pneumonia.

PURPOSE: To develop and validate a nomogram integrating chest computed tomography (CT) features and serum biomarkers for predicting the mutation status of macrolide resistance genes in pediatric Mycoplasma pneumoniae pneumonia (MPP).

METHODS

This retrospective study enrolled children diagnosed with MPP, genetically stratified into macrolide-resistant (MRMP) and macrolide-sensitive (MSMP) groups based on 23S rRNA gene mutations (A2063G/A2064G). Clinical data, chest CT scans obtained within 48 h of admission, and serum biomarker levels (including C-reactive protein [CRP], procalcitonin [PCT], interleukin-6 [IL-6], D-dimer, neutrophil-to-lymphocyte ratio [NLR], and lactate dehydrogenase to albumin ratio [LAR]) measured within 24 h of admission prior to antibiotic therapy were analyzed.

RESULTS

Compared to the MSMP group (n = 283), the MRMP group (n = 145) had longer fever duration (5.91 vs. 4.85 days) and hospital stay (8.77 vs. 7.32 days), higher rates of shortness of breath (35.86% vs. 24.38%) and oxygen requirement (25.52% vs. 13.78%), elevated serum levels of CRP (39.16 vs. 31.74 mg/L), D-dimer (1.51 vs. 1.32 mg/L FEU), NLR (6.15 vs. 5.22), PCT (0.55 vs. 0.35 ng/mL), IL-6 (28.86 vs. 21.35 pg/mL), and LAR (9.19 vs. 8.42), and more frequent CT findings of lobar consolidation (68.28% vs. 45.23%), bilateral involvement (66.21% vs. 51.59%), pleural effusion (32.41% vs. 14.49%), and higher total severity score (9.22 vs. 7.88). The nomogram based on these independent predictors showed excellent discrimination with an area under the curve of 0.869.

CONCLUSION

A nomogram combining CT imaging characteristics and serum biomarkers predicted mutation status of macrolide resistance genes in pediatric MPP, potentially aiding early clinical decision-making.