Occurrence of Bronchial Anthracofibrosis in Respiratory Symptomatics with Exposure to Biomass Fuel Smoke

Introduction: Bronchial anthracofibrosis (BAF), confirmed bronchoscopically, is characterised by bluish-black mucosal pigmentation and distortion/narrowing of the bronchus. We investigated the occurrence of BAF in respiratory symptomatics with biomass fuel smoke exposure and evaluated its clinico-radiological attributes and impact on functional status. Material and methods: Of the eighty subjects evaluated, 60 consented for fiberoptic bronchoscopy (FOB). All 60 subjects also underwent chest radiography, high resolution computed tomography (HRCT) of the thorax, spirometry with reversibility testing and six-minute-walk test. Information regarding cardinal respiratory symptoms and duration of biomass fuel smoke exposure was documented. FOB evaluation revealed that 24 patients had BAF (Group 1), 17 had bronchial anthracosis (Group 2) and 19 had normal appearance (Group 3). Results: Group 1 patients had significantly higher biomass fuel smoke exposure (p < 0.0001) and lower walk distance (p = 0.003) with greater desaturation. On HRCT, segmental collapse and consolidation were significantly higher in Group 1 while fibrotic lesions were the predominantly seen in Groups 2 and 3. A significant inverse correlation in Group 1 was seen between exposure index, six-minute-walk distance and spirometric parameters. In Group 1, the right middle lobe (RML) bronchus was most commonly involved (15/24 [62.5%]). In Group 2, RML and left upper lobe bronchi were affected in 8/17 (47.1%) patients each. Conclusions: All patients in our study were females. Those with BAF had poorer functional status as compared to those with anthracosis only. On imaging, multifocal bronchial narrowing was specific to BAF.