Abstract Background: Meningitis is an inflammation of the protec-tive membranes covering the brain and spinal cord. Acute meningitis could be life-threatening condition because of the inflammation's proximity to the brain and spinal cord. There-fore, immediate diagnostic and therapeutic procedures were required. Aim of Study: This study aimed to assess the diagnostic usefulness of measuring cerebrospinal fluid (CSF) calprotectin level indiagnosis of acute meningitis and its value in differ-entiation between bacterial and nonbacterial (aseptic) acute meningitis. Patients and Methods: This study conducted on 90 sub-jects, sixty patients represented to Shebin El-Koum Fever Hospital with acutely suggesting symptoms of meningitis (fever, severe headache, altered mental status, avoid bright light and stiff or painful neck) in whom lumber puncture was done and CSF conventional laboratory finding like WBCs count, glucose and protein were measured, these patients were divided into, group 1: Thirty patients with CSF laboratory finding of bacterial meningitis, group 2: Thirty patients with CSF laboratory finding of aseptic meningitis and group 3: Thirty cross age and sex matched non-meningitc subjects undergoing spinal anesthesia for non-neurological surgical causes as acontrol group. The concentration of CSF calprotectin was determined by ELISA in all the studied cases. Results: CSF calprotectin mean level was 10.2±SD 2.36 ng/ml in patients with bacterial meningitis, 8.7±SD 1.91 ng/ml inaseptic meningitis while, in the control group was 6.5±SD 1.45ng/ml with statistically significant difference (p < 0.01) between all groups. Performance of CSF calprotectin in diagnosis of aseptic meningitis at a value 7.42-9.03ng/ml by ROC curve parameter had sensitivity 60%, specificity 60%, PPV 60%, NPV 60%, AUC: 0.68 with 95% CI, 0.55-0.82. While at a value more than 9.03ng/ml, CSF calprotectin had-sensitivity 80%), specificity (70%), PPV 72.7%, NPV 77.8%, AUC: 0.81 with 95% CI, 0.72-0.90 in diagnosis of bacterial meningitis.
Conclusions: CSF calprotectin may serve as a potential diagnostic marker of acute meningitis and its determination could be usefulin differentiation between bacterial and aseptic meningitis.