BackgroundNosocomial meningitis is a medical emergency that requires early diagnosis, prompt initiation of therapy, and frequent admission to the intensive care unit (ICU).MethodsA retrospective study was conducted in adult patients diagnosed with nosocomial meningitis who required admission to the ICU between April 2010 and March 2020. Meningitis/ventriculitis and intracranial infection were defined according to Centers for Disease Control and Prevention guidelines.ResultsAn incidence of 0.75% of nosocomial meningitis was observed among 70 patients. The mean patient age was 59 years and 34% were ≥65 years. Twenty-two percent of patients were in an immunocompromised state. A clear predisposing factor for nosocomial meningitis (traumatic brain injury, basal skull fracture, brain hemorrhage, central nervous system [CNS] invasive procedure or device) was present in 93% of patients. Fever was the most frequent clinical feature. A microbiological agent was identified in 30% of cases, of which 27% were bacteria, with a predominance of Gram-negative over Gram-positive. Complications developed in 47% of cases, 24% of patients were discharged with a Glasgow coma scale <14, and 37% died. There were no clear clinical predictors of complications. Advanced age (≥65 years old) and the presence of complications were associated with higher hospital mortality. ConclusionsNosocomial meningitis in critical care has a low incidence rate but high mortality and morbidity. In critical care patients with CNS-related risk factors, a high level of suspicion for meningitis is warranted, but diagnosis can be hindered by several confounding factors.