Abstract Plastic bronchitis is a rare condition where rigid casts develop in the tracheobronchial tree resulting in airway obstruction. Incidence ranges from 4-14% however, is described frequently in patients with cardiac disease or chronically decreased pulmonary clearance. Plastic bronchitis maintains high morbidity and mortality with limited treatment options. We present a case in which casts were successfully removed with nebulized tissue plasminogen activator (tPA). A 2-year-old female with postinfectious necrotizing hemorrhagic encephalopathy without tracheostomy or cardiac defects presented with hypoxic respiratory failure, one week of upper respiratory symptoms, and fever. Her condition deteriorated despite continuous albuterol, terbutaline, and BiPAP and required intubation. She became difficult to bag with no chest rise, severe desaturation, and loss of end-tidal. The endotracheal tube was removed and a cast was found at the end. Bronchoscopy revealed a cast completely obstructing the left mainstem bronchus. The cast could not be retrieved given size limitations of the working channel of the bronchoscope (Olympus XP 190, 2.8mm- 1.2mm). 2mg of tPA was directly applied to the cast with 20% of the cast removed. Bronchoscopy was reattempted in 4 hours with reapplication of tPA and again only a small portion of the cast was removed. She was started on inhaled tPA, 5mg- 0.269 mg/kg every 8 hours. Approximately 18 hours later, bronchoscopy revealed complete resolution of the cast. Nebulized tPA was continued with improvement in respiratory status and weaning of ventilator settings. Second cast obstructing 60% of the left mainstem bronchus was found and removed. Pathology revealed a cellular cast with lymphocytes, macrophages, and neutrophils. The patient continued to decompensate. Bronchoscopy demonstrated significant inflammation but no evidence of mucus plugging or casts. She was ultimately transferred to a tertiary facility for ECMO. Two types of bronchial cast have been described. Type 1, or inflammatory casts, are composed of fibrin and eosinophils and seen in patients with cystic fibrosis and severe asthma. Type 2, or acellular casts, are composed of mucin with little or no cellular components and seen almost exclusively in patients with cardiac defects, specifically as a complication following Fontan repair. Our patient had cellular casts on bronchoscopy. This poses continued questions regarding cast development given the subacute presentation rather than chronic accumulation due to chronic disease. Additionally, this case provides support for nebulized tPA, along with aggressive pulmonary clearance, in short and long-term management of plastic bronchitis, particularly with size limitations of the pediatric bronchoscope’s working channel. This abstract is funded by: None
Yackley et al. (Fri,) studied this question.