Inclusion Criteria:  Patient admitted to the Adult Emergency Department of CH Le Mans,CHU Angers, CHU Nantes or Beaujon Hospital. Over 18 years old Having had a lumbar puncture during their stay in the Adult Emergency Department Having had a diagnosis of meningitis defined as a pleocytosis ≥ 5leukocytes/mm3 after correction with CSF red blood cells at a standardized ratio of 500/1.  Exclusion Criteria:  Antibiotic therapy within 72 hours of inclusion Immunosuppression from any cause Presence of petechiae or purpura History of recent neurosurgery or head trauma Other associated bacterial infection Inability to collect information for the BMS score calculation or primary endpoint (e.g., transfer to another facility) Minor or adult patient under guardianship or protection