Predictors of mortality in CNS tuberculosis: clinical and radiological parameters.

BACKGROUND: Central nervous system tuberculosis (CNS-TB) is a rare but highly lethal form of TB with heterogeneous clinical and radiological features. We evaluated objective clinical grading, CSF indices, and MRI findings associated with in-hospital mortality.

METHODS: In this single-center retrospective cohort (2010-2023), all consecutive adults with CNS-TB were included (n = 15). Patients were grouped as survivors (n = 6) and non-survivors (n = 9). We extracted BMRC stage, baseline GCS, symptom-to-presentation and symptom-to-treatment durations, CSF cyto-biochemistry and microbiology (culture/PCR), and a standardized MRI checklist (basal exudates, hydrocephalus, ventriculitis, infarcts, tuberculoma/abscess, cranial nerve enhancement, spinal involvement). Treatment protocols (ATT, dexamethasone indications, neurosurgery) were documented. Results are primarily reported as counts/proportions with exploratory effect sizes.

RESULTS: The mortality rate was 60%. Non-survivors were significantly older (57.8 ± 22.8 vs. 29.2 ± 6.9 years; P = 0.029, d = 1.56) and had higher serum AST levels (28.9 ± 6.4 vs. 15.0 ± 2.9 U/L; P = 0.007, d = 2.14). CSF leukocyte count was also significantly elevated in non survivors (P = 0.041, d = 0.95). Cerebral ischemia was present only in non-survivors (56% vs. 0%; P = 0.04, h = 0.98). PCR positivity in non-CSF samples (0% vs. 78%) was significantly associated with mortality (P = 0.007). Other parameters showing moderate to large effect sizes included focal neurological deficits, ventriculitis, and increased CSF opening pressure.

CONCLUSIONS: Advanced age, elevated AST levels, increased CSF leukocyte count, cerebral ischemia, and extraparenchymal PCR positivity emerged as major predictors of mortality in CNS-TB. These factors may aid early risk stratification and treatment planning. Larger prospective studies are warranted to validate these findings.