title: Comparison of samples obtained from bronchoscopy of patients with and without bronchial anthracosis for investigating the prevalence of Mycobacterium tuberculosis.
abstract: OBJECTIVE
  Bronchial anthracosis is caused by the deposition of carbon, silica or asbestos particles in mucosal and submucosal cells and macrophages, and it can lead to chronic bronchial obstruction. Certain studies have reported an association between bronchial anthracosis and infection with Mycobacterium tuberculosis. This study aimed to compare the samples obtained from bronchoscopy of patients with and without bronchial anthracosis for investigating the prevalence of Mycobacterium tuberculosis.
  
  
  METHODS
  This was a cross-sectional study conducted between 2010 and 2013. A total of 514 patients underwent diagnostic bronchoscopy for pulmonary diseases. A sample of bronchoalveolar lavage fluid was taken from each patient and tested for Mycobacterium tuberculosis through smear and culture techniques. The data were analyzed with Chi-square and Fisher's exact test, with p ≤.05 set as the significant level.
  
  
  RESULTS
  Totally, 514 patients were evaluated through bronchoscopy; bronchial anthracosis was diagnosed in 207 cases, of which 129 (62.3%) were women. The rate of pulmonary tuberculosis was significantly higher (p = .002) in the bronchial anthracosis group.
  
  
  CONCLUSIONS
  In our study, the prevalence of pulmonary tuberculosis was significantly higher in the bronchial anthracosis group. Given that pulmonary tuberculosis is still one of the health problems of the present century, increased attention to specific risk factors including bronchial anthracosis in patients having pulmonary symptoms is recommended.
authors.affiliation: MD, Internal Medicine Departments, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Samet
authors.affiliation: MD, Infectious Diseases Research Center, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
authors.forename: Jamshid
authors.initials: J
authors.lastname: Ayatollahi
authors.affiliation: GP, School of Medicine, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
authors.forename: Atefeh
authors.initials: A
authors.lastname: Aboutorabi
authors.affiliation: MD, Internal Medicine Departments, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
authors.forename: Masoud
authors.initials: M
authors.lastname: Rahimian
authors.affiliation: MSc, Infectious Diseases Research Center, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
authors.forename: Seyed Hossein
authors.initials: SH
authors.lastname: Shahcheraghi
authors.affiliation: PhD, Department of Medical Genetics, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
authors.forename: Seyed Alireza
authors.initials: SA
authors.lastname: Mirjalili
keywords: Bronchial anthracosis; Mycobacterium tuberculosis; bronchoscopy