Mycobacterium Avium Complex Pneumonia Mimics Lung Cancer Nodules But Improves after Antibiotic Therapy

Abstract

Infection with non-tuberculous mycobacterium species commonly can present with lung nodules mimicking lung cancer on routine chest imaging. The authors report three representative cases in which a suspected Mycobacterium avium-intracellulare complex infection was discovered incidentally that mandated evaluation for potential malignancy. After suspecting that the nodules were likely infectious and not malignant, the patients were empirically treated with azithromycin alone or in combination with other antibiotics. In each case, this treatment improved the appearance of these nodules on radiographic imaging in size, density, or both. These cases present typical examples of an increasingly prevalent infection commonly seen that can be mistaken for lung cancer, particularly in endemic areas. Many non-malignant etiologies are capable of mimicking lung cancer including the most common, nontuberculous mycobacterium. Recognizing probable infectious lung nodules may prevent invasive and expensive clinical evaluations.

Note:
Funding declaration: None.

Conflict of Interests: The authors declare no real or potential conflicts of interest.

Ethics Approval Statement: Written informed consent was obtained from the patients for publication of this case report and accompanying images.

Keywords: Lung nodules, Mycobacterium avium complex, lung cancer