Black lungs and big nodes: A case of airway anthracosis with bronchial anthracofibrosis

摘要

We present a case of a 76 year-old, non-smoking Honduran female who was referred to our clinic for years of persistent dry cough. Cardiac evaluation was unremarkable. She denied symptoms of heartburn, allergic rhinitis, and there was no personal or family history of asthma. Her physical exam demonstrated wheezing over the right mid-posterior chest. Spirometry was within normal limits. CT-imaging of the chest demonstrated right middle lobe bronchus and lingular segmental bronchus narrowing with bibasilar atelectasis and mild interlobular septal thickening with prominent mediastinal adenopathy. Bronchoscopy showed diffuse airway hyperpigmentation, right middle lobe medial segmental bronchial stenosis and lingular segmental bronchial stenosis. Endobronchial ultrasound demonstrated enlarged mediastinal lymph nodes, and transbronchial needle aspirates revealed necrotic tissue with black anthracotic pigment. Cultures were negative. Post-procedurally, the patient revealed regular use of a wood stove in an enclosed, poorly-ventilated kitchen. Anthracosis is the black discoloration of bronchial mucosa due to deposition of carbon-based particles in the airway, usually related to chronic environmental exposures. It can eventually result in endobronchial and parenchymal fibrosis and is mostly seen in non-smokers. Burning biomass fuel from wood smoke is a risk factor in the developing world. Symptoms include cough, dyspnea, and wheezing. Spirometry will usually demonstrate obstruction. CT-based imaging can show intraluminal narrowing, predominantly affecting the right middle and right upper lobe bronchi, resulting in distal segmental collapse. Extrapulmonary findings are rare, but usually are in the form of calcified mediastinal adenopathy on CT-based imaging, which allows for differentiation from lung cancer. There is no reliable treatment though bronchodilators can achieve clinical benefit.