Bronchial Anthracosis and Pulmonary Tuberculosis

Background: Bronchial anthracosis is defined as appearance of multiple dark anthracotic pigmentations on large airway mucosa with or without airway narrowing or obliteration. Since there has been vague and controversy regarding the relationship between bronchial anthracosis and pulmonary tuberculosis, we conducted this study to shed light on this matter.Materials and Methods: In this cross-sectional study, data was obtained from reviewing the files of 1,594 patients who underwent bronchoscopy in Afzalipour Hospital during 2003 to 2007. Those with dark pigmentation on their airways mucosa were considered as having bronchial anthracosis. During bronchoscopy, samples were collected from the airways in the form of bronchoalveolar lavage and then the smear and culture of these samples were examined for acid fast bacilli. Patients with both positive culture and smear and those with positive culture alone for acid fast bacilli were considered as having pulmonary tuberculosis.Results: Of 1,594 cases studied in this research, 333 (20.8%) had bronchial anthracosis, out of which 158 (55.5%) were women. Risk of bronchial anthracosis was 0.4 times less in men (CI 95%=0.32-0.52) (p 0.001). In other words, bronchial anthracosis had a significantly less prevalence among men. Also, risk of tuberculosis in people with bronchial anthracosis was 2.6 times more than that of healthy people (CI 95%= 1.48-4.75) (p 0.001).Conclusion: This research revealed a significant correlation between bronchial anthracosis and pulmonary tuberculosis. Therefore, performing necessary tests and follow-ups for pulmonary tuberculosis is necessary in cases that undergo bronchoscopy for any reason and those with bronchial anthracosis.