Pulmonary tuberculosis presenting as an enlarging left lower lobe mass-like lesion mimicking malignancy

nucleic acid amplification testing (NAAT) was positive; AFB smear was positive and culture confirmed fully susceptible TB. The patient was managed with airborne isolation precautions and started on rifampin, isoniazid, pyrazinamide, and ethambutol (RIPE), with rapid clinical improvement. Follow-up CT was deferred at the patient's request due to concerns about cumulative radiation exposure, given his significant symptomatic recovery. This case reinforces maintaining TB on the differential diagnosis of enlarging lung masses-particularly in patients with epidemiologic risk factors and immunometabolic comorbidity-and highlights the value of repeat sampling, tissue diagnosis, and NAAT in atypical presentations.