Tuberculous brain abscess mimicking metastatic disease

An 85-year-old, HIV-seronegative woman presented with subacute right-sided weakness and dysarthria. Neuroimaging revealed multiple rim-enhancing intracranial mass lesions, initially attributed to metastatic disease of unknown primary. Subsequent biopsy and excision yielded purulent material with abundant acid-fast bacilli; culture and molecular testing confirmed Mycobacterium tuberculosis. Histopathology demonstrated an exceptionally high mycobacterial burden and an absence of well-formed epithelioid granulomas, establishing a diagnosis of tuberculous brain abscess. A 12-month anti-tuberculosis therapy led to clinical and radiological resolution. This case illustrates an uncommon presentation of central nervous system tuberculosis that can closely mimic intracranial malignancy.