Suspected Occult Malignancy Revealing Pulmonary Mycobacterium chimaera Infection
DOI:
https://doi.org/10.60591/crspmi.561Keywords:
Bronchiectasis, Mycobacterium chimaera, Mycobacterium Infection, Neoplasms/complications, Nontuberculous Mycobacteria, Weight LossAbstract
Mycobacterium chimaera is a slow-growing non-tuberculous mycobacterium of the Mycobacterium avium complex that may mimic malignancy or systemic inflammatory disease due to its non-specific presentation.
We report an elderly woman with significant weight loss (27% over two years), anorexia and asthenia, initially attributed to dementia and later suspected to represent an underlying occult malignancy. After exclusion of neoplastic and autoimmune causes, thoracic computed tomography showed bronchiectasis and a tree-in-bud pattern. Bronchoscopy confirmed Mycobacterium chimaera infection. She was treated with azithromycin, rifampicin and ethambutol for 12 months, with a favourable clinical and radiological response.
This case highlights the importance of considering non-tuberculous mycobacterial infection in unexplained weight loss, even in the absence of classical risk factors.
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Copyright (c) 2026 Sofia Brasil, João Couto, Christine Canizes, João Vítor Vieira, José Seabra de Brito, João Rocha Gonçalves

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