Abstract Rationale Characterization of bronchial inflammation by endobronchial biopsy (EBB) opens a diagnostic window in children with severe uncontrolled asthma and is traditionally performed with forceps (EBFB). The flexible cryoprobe offers a new interventional modality within the pediatric interventional bronchoscopy space. We report our experience with endobronchial cryobiopsy (EBCB) comparing safety and clinical diagnostic utility to EBFB in children with severe uncontrolled asthma. Methods We performed a retrospective chart review of consecutive pediatric patients who underwent flexible bronchoscopy with EBB as part of the evaluation of severe uncontrolled asthma in accordance with our protocol from October 2023 through June 2025. Bronchoscopy reports, bronchoalveolar lavage results, and pathology reports were reviewed for procedural complications, biopsy specimens’ size, and the number of required specimens for each patient. Diagnostic utility was assessed by presence of epithelial layer, reticular basement membrane, and inflammatory cells. Results Eighty-eight cases were reviewed, 57 (65%) were male, and the average age was 7.6 years (0-20 years). EBCB was performed with 1.7mm cryoprobe in 43 patients and EBFB with 2mm forceps in 45. There were no differences in age (8.4 vs. 6.9 years; p=0.137) or sex (65.1% vs. 64.4% male). There was one case of bleeding following EBCB that required return to the procedure room and repeated application of topical dilute oxymetolazone. EBCB samples were larger than EBFB, 4.0mm vs 2.9mm (p=0.028) and provided adequate tissue with fewer samples (single sample: 67.4% vs. 48.9%, p=0.026). The diagnostic utility was high with both EBCB and EBFB (98% and 96%). EBCB showed eosinophils more frequently (32.6% vs. 8.9%, p=0.006). CONCLUSIONS EBCB with the 1.7mm cryoprobe is safe, effective, and diagnostic in children with severe uncontrolled asthma. EBCB yields diagnostic information with fewer samples and allows for better detection of the eosinophilic pattern of inflammation, which may be related to the larger specimen size. Bleeding complications were rare. Further studies are needed to evaluate the diagnostic yield and complications for EBCB with 1.1mm cryoprobe compatible with smaller pediatric bronchoscopes. This abstract is funded by: None
Patel et al. (Fri,) studied this question.