The Bacterial Meningitis Score (BMS) for children is a clinical calculator used to identify pediatric patients (from 29 days to 19 years old) at very low risk of bacterial meningitis. This scoring system is particularly useful in distinguishing bacterial from viral meningitis, which can help guide treatment decisions and potentially avoid unnecessary hospitalization or antibiotic use. The BMS includes five criteria: positive cerebrospinal fluid (CSF) Gram stain, CSF protein ≥80 mg/dL, CSF absolute neutrophil count (ANC) ≥1000 cells/mm³, peripheral blood ANC ≥10,000 cells/mm³, and seizure at or prior to presentation. Each positive criterion increases the likelihood of bacterial meningitis. The BMS should not be used in patients with a ventriculoperitoneal shunt or recent neurosurgery, as these conditions can alter the CSF parameters and potentially lead to a false score.

Bacterial meningitis score for children

# Criteria
 A. CSF Gram stain positive (+1)
B. CSF ANC >= 1,000 cells/mcL (+1)
C. CSF protein >= 80 mg/dL [800 mg/L] (+1)
D. Peripheral blood ANC >= 10,000 cells/mcL (+1)
E. Seizure at or prior to presentation (+1)

# Conditions
- score == 0
- score >= 1