Spectrum and outcome predictors of central nervous system infections in a neurological critical care unit in India: a retrospective review

Background There are few published studies on the spectrum and outcome of central nervous system (CNS) infection in the neurology intensive care unit (NICU). We report the spectrum of CNS infections in the NICU and the predictors of outcome. Methods During 2011 to 2012, 235 critically ill neurological patients were admitted to a 12-bed NICU in a tertiary-care teaching hospital in Lucknow, northern India; 76 (32.3%) of them had CNS infections and were included in the present study. The patients' demographic and clinical details were noted, together with the underlying aetiology, Glasgow Coma Scale (GCS) score, Acute Physiology and Chronic Health Evaluation (APACHE II) score, systemic inflammatory response syndrome (SIRS) and complications during mechanical ventilation. Deaths were recorded, and 3-month functional outcome in the surviving patients assessed by the modifed Rankin Scale (mRS). Results The median age of the patients was 37.5 (4-75) years and 31 were females; 36/76 (47%) patients had tuberculous meningitis, 28/76 (37%) viral encephalitis, 8/76 (11%) pyogenic meningitis and 4/76 (5%) fungal meningitis. Seven of these patients had AIDS. The median duration of mechanical ventilation was 8 (1-121) days and 39/76 patients (51.3%) died. Duration of hospital stay (OR 1.2, 95% CI 1.05-1.37, p=0.006) and duration of mechanical ventilation (OR 0.81, 95% CI 0.68-0.95, p=0.01) were independent predictors of death. At 3-month follow-up, 23/37 patients (62%) had recovered well, 10/37 (27%) were severely disabled and 4/37 (11%) had died. Conclusion Of patients admitted to the NICU during the study period, one-third had a CNS infection. Half of those with a CNS infection survived, and predictors of death were prolonged mechanical ventilation and prolonged hospital stay.