Central Nervous System Tuberculosis Presenting as Ventriculitis in an Immunocompetent Patient: A Diagnostic Challenge

Although tuberculosis is commonly identified as a respiratory disease, its extrapulmonary manifestations, particularly in the Central Nervous System (CNS), pose significant diagnostic and treatment challenges. This report discusses a 73-year-old woman who presented with a month-long fever and two days of altered sensorium associated with lethargy and inappropriate verbal response. Magnetic resonance Imaging of her brain revealed disproportionate dilatation of ventricles suggestive of ventriculitis. Despite a negative Cerebrospinal Fluid Cartridge-based Nucleic Acid Amplification Test (CSF CB-NAAT), findings such as elevated protein, low glucose, lymphocytic pleocytosis, and raised adenosine deaminase suggested CNS Tuberculosis (CNS TB). She received highdose intravenous steroids, anti-epileptics, and Anti-Tubercular Therapy (ATT). After 21 days of hospitalisation, she was discharged with significant improvement. A year later, she was symptom-free, with no relapse. This case report elaborates on a clinical variant of TB infection and the diagnostic challenges posed.