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Identifying low-risk patients for bacterial meningitis in adult patients with acute meningitis
Yasuharu Tokuda1, Masahiro Koizumi, Gerald H Stein
1Center for Clinical Epidemiology, St. Luke's Life Science Institute, Tokyo, Japan. tokuyasu@orange.ocn.ne.jp
Objective:
To derive and validate a clinical prediction model with high sensitivity for differentiating aseptic meningitis (AM) patients from bacterial meningitis (BM) patients.
Methods:
We developed the model using the derivation cohort in a community rural hospital in Okinawa and assessed its performance using the validation cohort in a metropolitan urban hospital in Tokyo. There were 66 (39.5%) and 5 (17.9%) adult patients with BM among the derivation (n=167) and the validation cohort (n=28), respectively. Recursive partitioning analysis was used to determine the important classification variables and to develop a sensitive model to safely exclude BM.
Results:
The model produced high- and low-risk groups based on the following: 1) Gram stain, 2) CSF neutrophil percent < or =15%, 3) CSF neutrophil count < or =150 cells/mm(3), and, 4) mental status change. Among the derivation cohort, there were 65 patients with BM in the high-risk group (n=76), while only one patient with BM was noted (sensitivity, 99%) in the low-risk group (n=91). Among the validation cohort, there were 5 patients with BM in the high-risk group (n=7), while no patient was classified with BM (sensitivity, 100%) in the low-risk group (n=21).
Conclusion:
This simple and sensitive model might be useful to safely identify low-risk patients for BM who would not require antibiotic treatment.
Insights
This study developed a sensitive clinical prediction model to differentiate bacterial meningitis (BM) from aseptic meningitis (AM). The model accurately identifies low-risk patients, potentially avoiding unnecessary antibiotic treatment for bacterial meningitis.
Area of Science:
- Clinical prediction modeling
- Infectious disease diagnostics
- Neurology and critical care
Background:
- Distinguishing between aseptic meningitis (AM) and bacterial meningitis (BM) is critical for appropriate patient management.
- Bacterial meningitis requires prompt antibiotic treatment, while aseptic meningitis does not.
- Accurate and sensitive diagnostic tools are needed to guide clinical decisions and prevent overtreatment.
Purpose of the Study:
- To derive and validate a clinical prediction model with high sensitivity for differentiating AM from BM.
- To develop a tool that can safely identify patients with a low risk of bacterial meningitis.
Main Methods:
- A clinical prediction model was developed using recursive partitioning analysis on a derivation cohort from a rural hospital.
- The model's performance was validated using a separate cohort from an urban hospital.
- Key variables identified included Gram stain, CSF neutrophil percentage, CSF neutrophil count, and mental status change.
Main Results:
- The derived model demonstrated high sensitivity in both derivation (99%) and validation (100%) cohorts.
- In the derivation cohort, 99% of bacterial meningitis cases were correctly classified.
- In the validation cohort, 100% of bacterial meningitis cases were correctly classified, with no BM patients in the low-risk group.
Conclusions:
- A simple, sensitive clinical prediction model effectively differentiates bacterial meningitis from aseptic meningitis.
- This model can safely identify low-risk patients who may not require antibiotic therapy.
- The tool has potential utility in clinical settings to guide treatment decisions for meningitis.
Related Concept Videos
Bacterial Meningitis I: Introduction
Bacterial Meningitis
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Bacterial Meningitis II: Pathophysiology
Pneumonia III: Complications and Assessment
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