Bronchial anthracofibrosis and tuberculosis in immigrants to Canada from the Indian subcontinent.
BACKGROUND
Bronchial anthracofibrosis is a condition of proximal airway narrowing or obliteration and hyperpigmentation in persons with or without a history of occupational dust exposure. It is a bronchoscopic finding that is not uncommonly associated with pulmonary tuberculosis (PTB) in residents of South Korea, Iran and India. It is largely unrecognized in the Western world.


METHODS
We report the frequency of anthracofibrosis in foreign-born PTB patients who underwent bronchoscopy in two cities of Canada. We describe the composition of the pigment in the lungs of patients and speculate on the pathogenesis of anthracofibrosis-associated PTB.


RESULTS
Anthracofibrosis was present in 10/60 (16.7%) foreign-born patients who underwent bronchoscopy and had PTB between 2002 and 2006. Compared to patients from other Asian countries, patients from the Indian subcontinent were more likely to have anthracofibrosis (9/18, 50.0% vs. 1/26, 3.7%, P < 0.001). Carbonaceous particles, silica and silicates predominated in tissue specimens. Proximal airway narrowing appeared to be secondary to mixed dust- and smoke-related anthracofibrosis, PTB, or both.


CONCLUSIONS
Anthracofibrosis is not uncommon in immigrants to Canada from the Indian subcontinent with PTB. PTB may be a responsible or complicating condition in patients with anthracofibrosis.
Hwang
J
J
Department of Pathology, University of Alberta, Edmonton, Alberta, Canada.
Puttagunta
L
L
Green
F
F
Shimanovsky
A
A
Barrie
J
J
Long
R
R
D000368:Aged; D055008:Anthracosis / Q000453:epidemiology / Q000209:etiology / Q000473:pathology*; D001208:Asia / Q000208:ethnology; D001980:Bronchi / Q000473:pathology*; D001999:Bronchoscopy; D002170:Canada / Q000453:epidemiology; D004391:Dust; D005260:Female; D006801:Humans; D007194:India / Q000208:ethnology; D008297:Male; D008875:Middle Aged; D016273:Occupational Exposure / Q000009:adverse effects; D012189:Retrospective Studies; D012906:Smoke / Q000009:adverse effects; D014397:Tuberculosis, Pulmonary / Q000150:complications / Q000453:epidemiology / Q000473:pathology*
D004391:Dust; D012906:Smoke