Background and Objective: Bacterial meningitis is a serious disease with high rate of mortality and morbidity in children. Invasion of pathogens causes brain and meningeal inflammation, which leads to the release of biomarkers into cerebrospinal fluid (CSF). Identification of these biomarkers can help the physicians to differentiate between bacterial and aseptic meningitis. In the current study, some of these biomarkers such as Procalcitonin, C reactive protein (CRP), and Ferritin, were compared in cerebrospinal fluid (CSF) of patients with bacterial and aseptic meningitis.
Methods: In a prospective cross sectional study in a referral children hospital in Tehran during 2011- 2013, the CSF levels of Procalcitonin, Ferritin, and CRP were measured in 57 children with clinically suspected meningitis. The Mann-Whitney u test and the chi-square test were used to compare two groups, children with bacterial and aseptic meningitis. The cut-offs of biomarker levels for differentiation between the 2 groups were constructed by receiver-operating – characteristic curve (ROC).
Results: 57 subjects (30 bacterial and 27 aseptic meningitis), were enrolled in this survey. In comparing the two groups, the CSF levels of Ferritin, CRP, and procalcitonin in bacterial meningitis were significantly higher than in aseptic meningitis (P values=˂0.001, 0.001, ˂0.001respectively), with sensitivity/ specificity being 92.9% / 68%, 92.9% / 84%, and 96.4% / 80%, respectively. Positive Predictive Values (PPV) were, correspondingly, 96.4%, 92.8%, and 92.8% for procalcitonin, Ferritin, and CRP. Corresponding Negative Predictive Values (NPV) were, respectively equal to 95.4%, 70%, and 88%.
Conclusion: CSF of children with bacterial meningitis contains higher levels of inflammatory mediators including Procalcitonin, Ferritin, and CRP, compared to aseptic meningitis The biomarkers provided high sensitivity (especially PCT) and specificity (especially CRP). Using these complementary biomarkers would be useful for early diagnosis of bacterial meningitis and selection of appropriate treatment.
Keywords: CSF, CRP, ferritin, meningitis, procalcitonin, pathogens.