Clinical and pathological features and imaging manifestations of bronchial anthracofibrosis: the findings in 15 patients.

BACKGROUND

Bronchial anthracofibrosis (BAF) has been defined as a luminal narrowing associated with anthracotic pigmentation on bronchoscopy without a relevant history of pneumoconiosis or smoking. The aim of the study is to study the clinical features and imaging manifestations of BAF, and to promote the awareness of this disease.

METHOD

Between October 2006 and January 2012, 15 patients were diagnosed at our department as BAF that showed a narrowing or obliteration of lobar or segmental bronchi with anthracotic pigmentation in the overlying mucosa on bronchoscopy. The medical records including clinical features, imaging manifestations, electronic bronchoscopic findings, and pathological features were analysed, and the literature was reviewed.

RESULTS

A total of 15 patients were analyzed; 13 were female (86.7%) and two were male (13.3%) and the age range was from 62 to 86 years with a mean age of 74.5 years. Three cases (20.0%) had a history of tuberculosis. The most common clinical symptoms of BAF were cough (100%), expectoration (73.3%), dyspnea (60.0%), and fever (46.7%). Twelve cases displayed mild to moderate obstructive ventilatory dysfunction. In the electronic bronchoscopic evaluation, the most common findings were black bronchial mucosal pigmentation, bronchial stenosis, bronchial occlusion, and bronchial mucosal folds. Pathological evaluation revealed chronic inflammation of the bronchial mucosa, submucosal carbon particle deposition, and mucosal or submucosal fibrosis. Chest CT scans showed that 15 patients had bronchial stenosis or obstruction (direct signs) with the right middle lobe being the most common site (11 cases, 73.3%). The indirect sign was mainly the presence of bronchial obstructive diseases (including secondary infection), represented by 11 cases of pulmonary consolidation (73.3%), seven cases of atelectasis (46.7%), and five cases of nodules (33.3%). The CT mediastinal window showed bronchial lymph node lesions, mediastinal lymph node calcification (12 cases, 80.0%), and enlargement of multiple mediastinal lymph nodes.

CONCLUSIONS

The diagnosis of BAF was mainly based on bronchoscopic evaluation. Its pathogenesis is currently unclear, although it may be related to tuberculosis or bio-fuel inhalation. The diagnosis of BAF has important clinical significance, and improved awareness of this disease will contribute to prevention of unnecessary thoracotomies.