Importance of asking a social history: atypical pulmonary infections and occupational hazards

Abstract

Non-tuberculous mycobacteria (NTM) are ubiquitous in the environment, but NTM infection is limited to individuals with risk factors. We present a case of a 62-year-old man who presented with a 1 year history of cough and shortness of breath. History was notable for significant tobacco use and work as a sandblaster without the use of personal protective equipment. His chest X-ray showed bilateral upper lobe cavitary lesions, which were redemonstrated on chest CT. A sputum Gram stain was positive for acid-fast bacilli, but his tuberculosis QuantiFERON was negative. He was started on empiric tuberculosis treatment. Sputum cultures ultimately returned for Mycobacterium avium intracellulare complex, and treatment was narrowed to azithromycin, rifampin and ethambutol. The case highlights risk factors for NTM infection, notably for this patient, occupational exposures that likely lead to the development of pneumoconiosis. Healthcare providers should ask about occupational history and counsel patients about protection from occupational hazards.