B57-11 A Curious Case of Black Lung

Abstract Introduction Anthracosis is a condition characterized by carbon accumulation in lung tissue caused by dust, biomass smoke, or air pollution. The condition is commonly seen in coal workers with more recent reports showing prevalence in farmers. Anthracosis can lead to bronchial anthracofibrosis causing bronchial obstruction. Incidence is greater in developing countries partly due to greater exposure to wood fire smoke and other pollutants. Here we describe a unique case of anthracosis in a patient from Afghanistan. Case Presentation A 77-year-old male with past medical history of Type II Diabetes Mellitus with associated nephropathy, severe mitral regurgitation, and former history of tobacco use presented to the emergency department in acute hypoxic respiratory failure requiring supplemental oxygen by nasal cannula. Chest CT angiography was obtained demonstrating bilateral ground glass opacities most pronounced in the lingula, in addition to bilateral mediastinal and hilar lymphadenopathy. Patient was admitted to the hospital for treatment of community acquired pneumonia. He underwent bronchoscopy with endobronchial ultrasound (EBUS). The bronchoscopy demonstrated diffuse dark grey pigmented tissue in bilateral airways, which was inflamed and friable. There was noted bronchial airway obstruction from pigmented tissue build up, and extrinsic airway compression from lymphadenopathy. Endobronchial biopsy of pigmented tissue demonstrated abundant black pigment laden histiocytes, some containing birefringent crystal-like material consistent with mixed dust exposure/reaction. Infectious work up from the bronchoscopy and lymph node cytology were negative. Discussion Histologic findings in our patient are consistent with anthracosis. Although no source of exposure was reported, common environmental risk factors from developing countries such as woodfires may go under-reported. Due to lack of prevalence of anthracosis in the United States and general awareness of more obscure risk factors, pulmonologists should be mindful of suggestive bronchoscopic and pathologic findings. Our case illustrates that anthracosis is not limited to the airways but can also have lymphatic involvement. While smoke, coal, and other pollutants certainly increase the risk of malignancy, it should be noted that nodal anthracosis can mimic infection, inflammation, and malignancy as in our patient. Other etiologies of dark pigmented lung mucosa range from aspergillus infection and melanoma to amiodarone induced lung injury. A thorough history and physical is crucial in keeping a broad differential and making an accurate diagnosis. If there is a current environmental exposure suspected as the cause, it should be removed immediately. This abstract is funded by: none