[Clinical Profile and Prognostic Determinants in Central Nervous System Tuberculosis: An Observational Study from a Tertiary Neurology Centre in India.]

BACKGROUND AND OBJECTIVES: Central nervous system tuberculosis (CNS TB) is a major cause of neurological morbidity in developing countries, with diverse clinical presentations. This study aimed to characterize the demographic and clinical profile of patients with CNS TB at a tertiary neurology center in India and to identify key clinical, laboratory, and radiological predictors of prognosis. METHODS: A prospective observational study was conducted between August 2023 and January 2025 on 110 patients with CNS TB at a tertiary care center. Demographic, clinical, neuroimaging, cerebrospinal fluid (CSF), systemic laboratory data, and cartridge-based nucleic acid amplification test (CBNAAT) findings were analyzed. Functional outcome was assessed using the modified Rankin Scale at the 9-month follow-up. RESULTS: Of 110 patients, 56.4% were female; the mean age was 29.86 ± 11.23 years, with 84% being younger than 40 years. Common features included meningeal signs (92.7%), headache (90.9%), fever (88.2%), altered sensorium (83.6%), and seizures (33.6%). Cranial nerve palsies occurred in 28.2% patients, mainly the sixth nerve. Pulmonary TB was present in 23.6% patients. Neuroimaging showed tuberculomas (37.3%), hydrocephalus (27.3%), infarcts (20%), and basal exudates (11.8%). CSF analysis revealed lymphocytic pleocytosis (mean 173 cells/mm³), elevated protein (182.7 mg/dL), and low glucose (mean CSF/plasma ratio 0.31). CBNAAT was positive in 18.2% subjects, with 16.36% being rifampicin-sensitive and rifampicin resistance was observed in 0.9%. Poor outcome was associated with increasing age, longer duration of illness, cranial neuropathy, hydrocephalus, and paradoxical reaction. CONCLUSIONS: CNS TB in our cohort predominantly affected young adults and presented with classical meningeal features and diverse neuroimaging abnormalities. Microbiological confirmation remained limited, underscoring reliance on clinical-radiological diagnosis. Poor outcome was associated with increasing age, longer duration of illness, cranial neuropathy, hydrocephalus, and paradoxical reaction.