Background: The diagnosis of bacterial meningitis in children, especially in those who have already been treated, can be difficult. Inflammatory biomarkers such as presepsin (soluble CD14 subtype) and IL-6 have been shown to be useful in distinguishing bacterial infections from non-bacterial infections.
Objectives: This study aimed to evaluate the level of CSF concentrations of prespsin and IL-6 in the differentiation of bacterial meningitis from non-CNS infection patients, the cutoff values in bacterial meningitis diagnosis, and determine the clinical data of bacterial meningitis in children under the age of five.
Methods: Between April 2020 and September 2021, we included children up to the age of 5 who were admitted to Chiang Mai University Hospital and Nakornping Hospital and underwent lumbar puncture for the examination of central nervous system infection. Children with recent intracerebral/intraventricular hemorrhage, HIV infection, hematologic malignancy, chronic kidney illness, or secondary immunodeficiency (occurring during immunosuppressive medication treatment) were excluded. The patients were divided into three groups: bacterial meningitis, other CNS infection, and non-CNS infection groups. The serum was obtained for CBC, blood sugar, and hemoculture, and the CSF was collected for protein, sugar, cell counts, gram stain, culture, and presepsin, as well as the IL-6 level. The enzyme-linked immunosorbent assay kit and chemiluminescent enzyme immunoassay were used to determine IL-6 and presepsin, respectively.
Result: Sixty-seven patients met the inclusion criteria; 31 were males (46%) and the median age was 27± 319.78 days (range 0-1460 days). Divided into three group: six with bacterial infection, eight with other CNS infection and fifty-three with non-CNS infection group. Forty-five (67%) children had a history of prior antibiotics treatment with mean duration to lumbar puncture is 30.64 ± 47.19; 0-216 hours (+ SD; range). CSF examination revealed 16.4% of patients had pleocytosis; 44.8% had abnormal protein level for age; 15% had a low CSF/sugar ratio, and 10% had a low CSF sugar level (< 40 mg/dl). CSF bacterial cultures were negative in all cases. The mean CSF IL-6 and presepsin concentration in patients with bacterial meningitis were 29.12 and 1,752 pg/dL, respectively, and 13.61 and 2,179 pg/dL in the other infection group, and 9.57 and 193.04 pg/ml in the non-CNS infection group. CSF IL-6 and presepsin levels were considerably greater in patients with bacterial meningitis than in non-CNS infected patients (p < 0.05). However, no statistically significant relationship exists between CSF presepsin and Il-6 levels in bacterial meningitis or other CNS infection. According to ROC curve, IL-6 had a sensitivity, specificity, PPV, and NPV of 83.3%, 83%, 35.2%, 97.8% at a cutoff level of 17.87 pg/mL. Similarly, CSF prespsin demonstrated sensitivity, specificity, PPV, and NPV of 83.3%, 96.2%, 71.1%, 98.1% at a cutoff level of 555 pg/mL.
Conclusions: The increased presepsin and IL-6 concentrations in the CSF of children with bacterial meningitis indicate that these biomarkers may have a diagnostic role and may be a useful marker for differentiating bacterial meningitis from non-CNS infections, especially in pre-treated patients. However, additional research is needed to determine the use of these inflammatory markers in diagnosing other CNS infections.
Keywords: Bacterial meningitis, IL-6, presepsin, cerebrospinal fluid, CNS infection
