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Updated: May 2, 2026

Measuring Carbon Content in Airway Macrophages Exposed to Carbon-Containing Particulate Matters
Published on: July 12, 2024
Black-pigmented sputum
Rafael Martínez-Girón1, Joaquín Mosquera-Martínez2, Santiago Martínez-Torre3
1CFGS Anatomic Pathology and Cytology. Institute of Piedras Blancas-Asturias, Spain.
Abstract:
Black-pigmented sputum, also called "melanoptysis," is a symptom that may be observed in certain pathologies such us coal workers' pneumoconiosis (anthracosis). The cavitation and liquefaction of a fibrosed mass by an infectious process (tuberculosis, infections by anaerobes, etc.) or by ischemic necrosis may cause expectoration of a blackish secretion. We report the case of a patient with labor precedents as a coal worker, from whom abundant black sputum was obtained in the course of an incidental expectoration. Cyto-histological findings are shown and a differential diagnosis is established.
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