A 77-year-old male presented to his primary care provider with 2 weeks of productive cough and blood in his sputum. The patient had a history of positive Interferon-Gamma Release Assay (IGRA) testing and no major risk factors. Opacities in the chest X-ray led to a chest CT that showed tree-in-bud nodules. These results led to a referral to pulmonology, where sputum for mycobacterial cultures was collected. On day 14, yellow colonies were observed on the Lowenstein-Jensen slant. 

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