Chest radiographic phenotypes in post-tuberculosis lung disease: morphometric heterogeneity, functional outcomes, and implementation of scoring systems.

BACKGROUND: Post-tuberculosis lung disease affects 30-50% of TB survivors despite successful treatment, yet systematic post-TB screening and surveillance remain absent from most national TB programs. Radiographic heterogeneity predicts functional impairment, but relationships between radiographic phenotypes and functional outcomes remain incompletely characterized in high-burden TB settings. METHODS: This prospective cross-sectional study enrolled 500 TB survivors (6-60 months post-treatment). PRIMARY OUTCOME: radiographic phenotype classification (minimal-change/moderate-complexity/complex) and associations with pulmonary function impairment (FEV₁ <80% predicted). Chest radiography assessed cavitation, bronchiectasis, parenchymal opacification, architectural distortion via standardized morphometric scoring. Spirometry performed per ATS/ERS 2019 standards. Inflammatory biomarkers (hs-CRP, fibrinogen) measured. Radiographic inter-rater reliability assessed via ICC. Logistic regression identified independent predictors. RESULTS: Of 625 enrolled, 500 (80%) completed assessment. Radiographic phenotypes: minimal-change 31.2%, moderate-complexity 42.8%, complex 26.0%. FEV₁ % predicted: minimal-change 89.2 ± 10.4%, moderate 75.8 ± 14.2%, complex 46.2 ± 16.8% (p < 0.001). FEV₁ <80% predicted: minimal 11.5%, moderate 56.1%, complex 98.5% (p < 0.001). Radiographic inter-rater reliability excellent (ICC 0.84; 95% CI 0.81-0.87). Complex phenotype associated with FEV₁ <80% (aOR 28.48; 95% CI 10.12-80.04). Elevated hs-CRP present in 24.4% minimal-change versus 76.9% complex (p < 0.001). Inflammatory biomarkers mediated 55% of phenotype effect on function. CONCLUSIONS: Chest radiographic phenotypes robustly predict pulmonary function impairment in post-TB disease. Complex phenotypes show severe obstruction (98.5%) and elevated inflammation. Simple, protocol-based morphometric scoring (3.8 min per image, ICC 0.84 between trained readers) is feasible for resource-limited settings. Radiographic phenotyping enables risk stratification in TB survivors.