Background: Among children with tracheostomies, little is known about how respiratory culture results differ between states with and without acute respiratory infections (ARI), or the overall test performance of respiratory cultures. Objective: To determine the association of respiratory culture organism isolation with diagnosis of ARI in children with tracheostomies, and assess test characteristics of respiratory cultures in the diagnosis of bacterial ARI (bARI). Methods: This single-center, retrospective cohort study included respiratory cultures of children with tracheostomies obtained between 2010-2018. The primary predictor was ARI diagnosis code at the time of culture; the primary outcomes were respiratory culture organism isolation and species identified. Generalized estimating equations were used to assess for association between ARI diagnosis and isolation of any organism while controlling for potential confounders and accounting for within-patient clustering. A multinomial logistic regression equation assessed for association with specific species. Test characteristics were calculated using bARI diagnosis as the reference standard. Results: Among 3,578 respiratory cultures from 533 children (median 4 cultures/child, IQR: 1-9), 25.9% were obtained during ARI and 17.2% had ≥1 organism. Children with ARI diagnosis had higher odds of organism identification (aOR 1.29, 95% CI 1.16–1.44). When controlling for covariates, ARI was associated with isolation of H. influenzae, M. catarrhalis, S. pneumoniae, and S. pyogenes. Test characteristics revealed a 24.3% sensitivity, 85.2% specificity, 36.5% positive predictive value, and 76.3% negative predictive value in screening for bARI. Conclusion: The utility of respiratory culture testing to screen for, diagnose, and direct treatment of ARI in children with tracheostomies is limited.

To our knowledge, this is the first reported case of successful transbronchial biopsy via RB in a 5-year-old patient. The sample revealed a potential diagnosis, but more importantly, helped rule out an active infectious process and avoided an open lung biopsy which was being planned and would have otherwise been necessary to establish a diagnosis. We believe this technology can be used to increase the diagnostic yield of flexible bronchoscopy, particularly in the immunocompromised population as there is already evidence supporting image-guided bronchoscopy over conventional bronchoscopy in this population [(4)](#ref-0004). A notable limitation to RB is the size of the available bronchoscopes for robotic platforms (4.5 and 3.5 mm OD). In children, this may limit the capacity to sample more peripheral lesions via fine needle aspiration, as more lung tissue (relative to chest size) may be injured. In our case, the catheter tip was never as close to the lesion as it has been described in adults [(2)](#ref-0002). As the field of pediatric interventional pulmonology continues to develop, RB will likely be one of several options available for safe and high-yield diagnostic procedures.

This case illustrates another promising example of the recent advances within pediatric interventional bronchoscopy. As innovative medical therapies continue to make their way into the pediatric realm (e.g. a 1.1-mm flexible cryoprobe has been recently developed by Erbe), opportunities for novel approaches and techniques will continue to present themselves.