Discrimination between viral and nonviral meningitis by visually analyzed and quantitative electroencephalography

Area of Science:

• Neurology
• Infectious Diseases
• Diagnostic Imaging

Background:

• Meningitis diagnosis relies on clinical presentation and laboratory tests.
• Differentiating viral from nonviral meningitis is crucial for appropriate treatment.
• The utility of electroencephalogram (EEG) and Glasgow Coma Scale (GCS) in acute meningitis requires further investigation.

Purpose of the Study:

• To compare the diagnostic accuracy of visually analyzed EEG (VEEG), quantitative EEG (QEEG), and GCS in distinguishing viral from nonviral meningitis.
• To assess the predictive values and consistency of these diagnostic tools.

Main Methods:

• A prospective study involving 55 patients with confirmed meningitis (viral, bacterial, tuberculous, cryptococcal).
• EEG recordings and GCS scores were obtained within 48 hours of admission.
• Sensitivity, specificity, and predictive values of VEEG, QEEG, and GCS were calculated.

Main Results:

• VEEG and QEEG showed higher sensitivity (70-80%) than GCS (38%) for detecting nonviral meningitis.
• All three tests demonstrated high positive predictive values (≥94%) for nonviral meningitis.
• VEEG and GCS had 100% specificity for viral meningitis, while QEEG was 82%.
• Normal VEEGs were exclusively found in viral meningitis cases.
• Delta abnormalities on VEEG strongly indicated nonviral meningitis.

Conclusions:

• EEG, particularly VEEG, is a valuable and potentially underestimated diagnostic tool in acute meningitis.
• EEG provides complementary information to the GCS, improving diagnostic accuracy.
• Specific EEG patterns, like normal or delta abnormalities, aid in differentiating meningitis types.