Allergic Bronchopulmonary Aspergillosis in Patients With Prior Pulmonary Tuberculosis: A Study on the Burden, Clinic-Radiological Features, Treatment Outcomes and Comparison With Chronic Pulmonary Aspergillosis and Post-Tubercular Lung Disease Patients

Background: Post-tuberculosis lung disease (PTLD) is a precursor to Aspergillus-related lung diseases. While Chronic Pulmonary Aspergillosis (CPA) has been extensively studied in the background of tuberculosis, Allergic Bronchopulmonary Aspergillosis (ABPA) has been reported sporadically with limited information on its prevalence, clinical-radiological features, and treatment outcomes. Objective: This study, conducted in a high TB burden setting, aimed to address this knowledge gap by systematically evaluating ABPA in PTLD patients. Methods: This retrospective cohort study screened PTLD patients presenting with respiratory or constitutional symptoms persisting for more than 3 months. The objective was to report the prevalence, clinical-radiological-laboratory data, and outcomes of ABPA-PTLD compared to a cohort of CPA (CPA-PTLD) and patients with PTLD (PTLD only). Results: Out of a total of 1012 PTLD patients, ABPA was seen in 2.27%, CPA in 20.75% and Aspergillus sensitization in 0.7%. ABPA patients primarily presented with breathlessness (91.3%) and cough (82.6%) while haemoptysis (43.5%), weight loss (13%), and anorexia (21.7%) were also observed, albeit less commonly than in CPA-PTLD. Bronchiectasis (100%) and nodules (87%) were more frequent in ABPA-PTLD patients, whereas consolidation (21.7%), cavities (30.4%), pleural thickening (8.7%), and 'fungal ball' (9.1%) were also seen, although less commonly than in CPA-PTLD. Most patients received azoles (78%) as first-line therapy, with symptomatic improvement (partial/complete) observed in similar to 78%. Conclusion: ABPA may occur in PTLD patients, with specific clinical (e.g., haemoptysis) and radiological (e.g., cavity and fungal ball) features uncommon in other types of ABPA, but resembling other PTLD conditions. Future studies should focus on identifying differences in the natural course and appropriate treatment paradigms of ABPA-PTLD patients compared to ABPA occurring in asthma and cystic fibrosis patients.