The innovative diagnostic model facilitates the differentiation between non - tuberculous mycobacterial lung disease and pulmonary tuberculosis

Mingkun Qiao^1,2Miao Li^1,2Qi WenHui^3*Lei Xu^1,2Xiaohui Miao^1,2Chao Cui^1,2*

• ¹Tianjin Haihe Hospital, Tianjin, China
• ²Tianjin Institute of Respiratory Diseases, Tianjin, China
• ³Tianjin Medical University General Hospital, Tianjin, China

Objectives: To construct a differential diagnostic model for Non-Tuberculous Mycobacterial Lung Disease (NTM-LD) and Pulmonary Tuberculosis Lung Disease (PTB-LD). Methods: Retrospective analysis of 300 NTM-LD and 300 PTB-LD patients (pathogen-confirmed) was performed. Patients were randomly split into training (2/3) and validation (1/3) sets. CT imaging, clinical data, and symptoms were analyzed. Logistic regression identified significant discriminative features, followed by random forest modeling to develop a diagnostic tool with web-based calculator. Model performance was validated using the independent validation set. Results: Univariate and multivariate analyses identified key discriminative factors (P< 0.05): cough with sputum, hemoptysis, thin-walled cavities, centrilobular nodules, bronchiectasis, diabetes, and autoimmune diseases. The diagnostic model achieved 82.5% sensitivity and 85.5% specificity (ROC analysis), with validation showing 78% sensitivity and 85% specificity, confirming strong discriminative power and calibration. Conclusions: The model constructed based on patients' CT imaging, basic clinical data, and symptomatic signs demonstrates commendable performance in the differential diagnosis of NTM-LD and PTB-LD, offering a convenient and practical auxiliary tool for clinical practice.