The Bacterial Meningitis Score for children is designed to quickly assess the risk of bacterial meningitis by evaluating five key clinical indicators. Each indicator contributes equally, and their presence leads to a numerical score that guides interpretation.

To compute the score, consider these indicators:

- CSF Gram stain positive
- CSF Absolute Neutrophil Count (ANC) at or above 1,000 cells per microliter
- CSF protein level at or above 80 mg/dL (equivalent to 800 mg/L)
- Peripheral blood ANC at or above 10,000 cells per microliter
- Occurrence of a seizure at or prior to presentation

For each indicator present, assign a score of 1. The total score, which ranges from 0 to 5, is the sum of the contributions from these indicators. This table summarizes the scoring:

| Indicator                                        | Condition Met (True) | Score Contribution |
|--------------------------------------------------|----------------------|--------------------|
| CSF Gram stain positive                           | Yes                  | 1                  |
| CSF ANC ≥ 1,000 cells/mcL                         | Yes                  | 1                  |
| CSF protein ≥ 80 mg/dL [800 mg/L]                 | Yes                  | 1                  |
| Peripheral blood ANC ≥ 10,000 cells/mcL           | Yes                  | 1                  |
| Seizure at or prior to presentation               | Yes                  | 1                  |

Interpretation of the total score is straightforward:

- A score of 0 indicates the risk is "very low" for bacterial meningitis.
- A score of 1 or higher suggests the risk is "not very low."

This simple yet effective scoring mechanism assists clinicians by summarizing risk based on the presence of specific clinical conditions, aiding in making timely and informed decisions regarding further evaluation and treatment.

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