This single-center retrospective study examined longitudinal spirometry trends in 15 pediatric patients with post-infectious bronchiolitis obliterans (PIBO) diagnosed at Vanderbilt University Medical Center from 1998–2023, analyzing changes in FEV1, FVC, and FEV1/FVC z-scores over time and by inciting pathogen (adenovirus vs. others).
Over a median ~6.4 years of follow-up, FEV1 z-score showed no significant change (0.008/year; p=0.69), remaining near −3.8 throughout. FVC z-score improved significantly (+0.185/year; p=0.003), while FEV1/FVC declined (−0.143/year; p=0.004), indicating dysanaptic growth. Adenovirus-infected patients started with a much lower FVC z-score (−4.42 vs. −1.73; p=0.02) but showed accelerated FVC recovery (p<0.001). Notably, 44% (4/9) of tested patients had a positive bronchodilator response.
- Very small sample (n=15; only 11 with spirometry) from a single US center limits generalizability. - Clinical diagnosis without biopsy in most patients raises misclassification risk. - Adenovirus group included co-infections, making pathogen-specific effects difficult to isolate.
In children with PIBO, FEV1 is a stable marker of persistent airway obstruction and should be monitored long-term, while FVC improvement—especially in adenovirus cases—reflects dysanaptic parenchymal growth rather than true recovery. Clinicians should routinely test for bronchodilator responsiveness, as nearly half of tested patients responded.
Explore related topics
