Clinical course of children with postinfectious bronchiolitis obliterans with versus without comorbid bronchopulmonary dysplasia.

Background: Postinfectious bronchiolitis obliterans (PIBO) is a rare chronic obstructive pulmonary disease that occurs after a respiratory infection. Its diagnosis is generally based on clinical history, respiratory symptoms, and computed tomography (CT) findings.

Purpose: Here we evaluated the frequency of exacerbations, clinical progress, and inhaled corticosteroid (ICS) usage in children diagnosed with PIBO with or without comorbid bronchopulmonary dysplasia (BPD).

Methods: This retrospective observational study was conducted in Rouen, France. The inclusion criteria were as follows: child diagnosed with PIBO (history of respiratory infection, airway obstruction with no or poor response to bronchodilation treatment, and/or mosaic pattern or trapping on chest high-resolution CT) in 2009-2024 treated with intravenous corticosteroid pulses.

Results: Fifty-seven patients were included: 13 (23%) with BPD and 44 (77%) without BPD. The mean age at diagnosis was 7.0±3.6 months, with no significant intergroup difference. We observed a significant reduction in exacerbations following corticosteroid pulse treatment as soon as 6 months (P<0.001), with persistent effects observed up to 24 months (P=0.02). We also noted a reduced daily ICS dose starting at 12 months (P=0.03). Respiratory syncytial virus is the most commonly identified causative virus, followed by rhinoviruses and adenoviruses. The viral codetection rates were 18% and 61% in the BPD and non-BPD groups, respectively.

Conclusion: In our cohort, intravenous corticosteroid pulse treatment effectively treated PIBO, with a rapid and long-lasting reduction in exacerbations and ICS requirements. BPD was a significant comorbidity of PIBO.