Hemosiderin-Laden Macrophages in Bronchoalveolar Lavage Samples of Children with Bronchopulmonary Dysplasia.

OBJECTIVES: To evaluate the prevalence of hemosiderin-laden macrophages in children with bronchopulmonary dysplasia (BPD) and assess for an association between hemosiderin-laden macrophages and pulmonary arterial hypertension. STUDY DESIGN: Retrospective case-control study of infants and children with and without BPD who underwent bronchoscopy with bronchoalveolar lavage (BAL) the at Children's Hospital of Philadelphia between 2012 and 2021. RESULTS: BAL from 205 children with BPD and 106 controls without BPD matched for tracheostomy, infection, and age were reviewed for hemosiderin-laden macrophages. Seventy-one individuals (34.6%) with BPD had a BAL with 10% or more hemosiderin-laden macrophages compared with 3 (2.8%) controls (P < .0001; OR, 18.19; 95% CI, 5.57-59.41). Patients with pulmonary hypertension by echocardiogram (P = .04; OR, 3.69; 95% CI, 1.05-12.96) or an elevated mean pulmonary artery pressure during cardiac catheterization, rs (14) = 0.56, P = .04, were more likely to have elevated hemosiderin-laden macrophages on BAL samples less than 60 days from bronchoscopy. After adjusting for birth weight, gestational age, BPD grade, and age at the time of bronchoscopy using logistic regression, pulmonary hypertension was associated with a higher odds of hemosiderin-laden macrophages of 10% or more (P = .02; OR, 6.37; 95% CI, 1.28-31.87). No association was observed between hemosiderin-laden macrophages and sex, race, gestational age, birth weight, tracheostomy, or infectious studies. CONCLUSIONS: This retrospective study revealed increased hemosiderin-laden macrophages in BAL samples from patients with BPD and a significant association with pulmonary arterial hypertension. It is unclear whether elevated hemosiderin-laden macrophages within BPD contributes to the pathogenesis of lung and pulmonary vascular disease or is simply a biomarker of pulmonary arterial hypertension.

Three-dimensional printed realistic pediatric static and dynamic airway models for bronchoscopy and foreign body removal training.

For mastering bronchoscope handling, positioning, and directing of the bronchoscope in response to the intraluminal view provided by the bronchoscope camera, sufficient training is necessary, especially in infants and toddlers who have smaller airways, faster respiratory rates, and higher airway collapsibility. With the use of three-dimensional printing, we aimed to develop a set of anatomically accurate and low-cost airway models for teaching and training of bronchoscopy technique and foreign body removal: a translucent airway box model, a static airway model, and a dynamic airway model consisting of a flexible tree model connected to a pump that allows simulation of airway collapsibility during breathing. Computed tomography (CT) patient data of three different ages (1, 5, and 18 years of age) was imported into Materialise Mimics, segmented, and printed using VisoClear and soft Tango+ material. The models were evaluated by three pediatric pulmonology attendings for anatomical accuracy and usefulness for teaching and training. The translucent airway box model was preferred for the initial presentation of bronchoscope handling and learning anatomy in three dimensions. The static and flexible tree models were used to train bronchoscope handling and foreign body removal. The dynamic model provided the most realistic representation of a pediatric airway throughout the respiratory cycle with increased patency during inspiration and relative collapse during exhalation. Objective verification of anatomical accuracy and physiology of breathing motion was obtained by comparing CT scans of the model with original images and by application of 4D dynamic CT airway imaging protocols, respectively.