A diagnostic challenge: Pulmonary tuberculosis masquerading as cancer progression in a patient with prostate carcinoma

Diffuse alveolar hemorrhage (DAH) is a life-threatening condition with a broad differential diagnosis. Pulmonary tuberculosis (TB) rarely presents as DAH and poses a diagnostic challenge, especially in immunocompromised individuals. We report the case of a 74-year-old male with metastatic prostate carcinoma on abiraterone and corticosteroids who presented with acute hemoptysis and bilateral ground-glass opacities on high-resolution computed tomography scan. Initial workup, including autoimmune panel and infectious screening, was inconclusive. Bronchoalveolar lavage (BAL) GeneXpert Mycobacterium tuberculosis /rifampicin (MTB/RIF) assay detected MTB DNA (trace), confirming the diagnosis. The patient responded favorably to first-line anti-tubercular therapy and was discharged on home oxygen with close outpatient follow-up. Outpatient follow-up patient improved symptomatically and radiologically. This case highlights the importance of considering pulmonary TB in the differential diagnosis of DAH, particularly in immunocompromised patients. GeneXpert MTB/RIF from BAL specimens can be pivotal in establishing early diagnosis.