B47-04 Not Fantastic, Made of Plastic - A Case of Plastic Bronchitis

Abstract A 51y/o man with a ten-year history of unspecified, waxing and waning chronic hypoxemic respiratory failure with chronic productive cough was admitted from pulmonary clinic for an ambulatory oximetry test showing a 10L supplemental oxygen requirement. Prior to this visit, he had been evaluated and treated for suspected chronic hypersensitivity pneumonitis based on occupational exposure history and radiographic evidence of waxing and waning ground glass opacities (GGO’s). Prior evaluation included a surgical lung biopsy, multiple rounds of IV and tapering oral steroids over the years. On admission, his CT chest again showed centrilobular GGOs in all lobes as well as debris in the bronchus intermedius, RLL and RML bronchi noting that the endobronchial findings were not present on prior imaging. Within 24 hours of admission, he required intubation for progressive hypoxemic respiratory failure despite diuresis, high dose IV steroids, and broad-spectrum antibiotics. Following intubation, he underwent bronchoscopy showing patent left sided anatomy, but with 70% occlusion of bronchus intermedius with dense, thick white secretion suspicious for plastic bronchitis. This was retrieved via cryoprobe. Histopathological assessment showed this to be fibrin-predominant with macrophages and mucous consistent with plastic bronchitis. Following removal, he was successfully extubated. In the following days, he underwent an MRI lymphangiogram with interventional radiology which showed lymphopulmonary reflux with numerous abnormal channels around the mediastinal and hilar regions with leak into the large airways. Embolization was performed from the mid-thoracic duct extending to the upper abdomen. After this intervention, he had a rapid improvement in his oxygenation and was requiring only 1L of supplemental oxygen at rest and with exertion. He was discharged on a prednisone taper and continued to do well at home with tapering home oxygen needs. CT chest less than one month following lymphatic embolization showed improved airspace disease and no obvious proximal airway debris. His pulmonary function tests have been stable with borderline obstruction and normal diffusion, and he has since returned to work. To this point, he has not had any identifiable etiology of his thoracic duct leak such as trauma or prior surgery and is assumed to be a case of idiopathic plastic bronchitis. Plastic bronchitis’ non-specific presentation and the potential to present as multifocal recurrent GGOs can lead to increased morbidity and misdiagnosis. Although rare, this case demonstrates the need to consider plastic bronchitis in the differential diagnosis of recurrent GGOs and in certain scenarios evaluate the utility of pursuing lymphangiogram. This abstract is funded by: None