AN UNUSUAL CAUSE OF EXERTIONAL AND POSITIONAL DYSPNEA

Abstract

SESSION TITLE: Tuesday Medical Student/Resident Case Report Posters SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: 10/22/2019 01:00 PM - 02:00 PM INTRODUCTION: Endobronchial lesions can be caused by a wide range of potential etiologies including both benign and malignant lesions. Patients may present with cough, dyspnea, hemoptysis or post-obstructive pneumonia. Herein we describe a case of a rare type of endobronchial lesion causing exertional and positional dyspnea with hypoxemia. CASE PRESENTATION: A 65-year old male with a history of obstructive sleep apnea on nocturnal positive pressure ventilation and treated hepatitis C virus infection presented with a 1-year history of progressive dyspnea on exertion and orthopnea but without other cardiopulmonary symptoms. He required supplemental oxygen to maintain oxygen saturations greater than 88% during exertion and while at elevation, where he lived 2,500 feet above sea level. Pulmonary function tests and echocardiogram were normal. His lungs were clear on auscultation and physical examination was otherwise unremarkable. A chest radiograph was normal. Computed tomography of the chest (Figure 1c) was notable for an endobronchial lesion in the left upper lobe bronchus with associated mild focal bronchiectasis. On flexible bronchoscopy, a partially obstructing pedunculated tumor was seen in the apicoposterior segment of the left upper lobe (Figure 1a). During exhalation, the lesion completely obstructed the segment (Figure1b), demonstrating a “ball-valve” phenomenon. The tumor was cryo-excised and the remaining base was ablated with argon plasma coagulation. The airway was then balloon dilated and normal airway patency was restored (Figure 1d). Pathology revealed benign hyaline cartilage and mature adipose tissue consistent with a hamartoma. The patient had resolution of his hypoxemia and orthopnea post-procedure. DISCUSSION: While pulmonary hamartomas are the most common benign pulmonary tumors, they are rarely found endobronchially. This case was notable for the dynamic “ball-valve” bronchial obstruction with associated positional and exertional dyspnea and hypoxemia. Intermittent obstruction by a ball-valve mechanism during ventilation may lead to air-trapping, V/Q mismatch and hypoxemia as well as recurrent infection due to impaired mucous clearance. The intermittent and positional nature of the obstruction made it difficult to diagnose on routine chest imaging or pulmonary function tests. CONCLUSIONS: In patients with unexplained dyspnea, the presence of endobronchial lesions should be considered Reference #1: Cosío BG, Villena V, Echave-Sustaeta J, et al. Endobronchial hamartoma. Chest. 2002;122(1):202-205. DISCLOSURES: Speaker/Speaker's Bureau relationship with Boehringer-Ingelheim Please note: $5001 - $20000 Added 03/17/2019 by Jaime Betancourt, source=Web Response, value=Honoraria No relevant relationships by Jessica Channick, source=Web Response No relevant relationships by Scott Oh, source=Web Response