Tejesh Malla

Is Cerebrospinal Fluid C-reactive Protein a Better Tool than Blood C-reactive Protein in Laboratory Diagnosis of Meningitis in Children?

OBJECTIVES This study aimed to test whether C-reactive protein (CRP) measurement could differentiate between different types of meningitis and become a routine test. METHODS A prospective study included 140 children admitted to Manipal Teaching Hospital, Pokhara, Nepal, between July 2009 and June 2011. The subjects had a blood test and detailed cerebrospinal fluid (CSF) analysis, including blood and CSF CRP levels. RESULTS Of those admitted, 31.1% had pyogenic meningitis (PM), 26.2% partially treated meningitis (PPM), 33% viral meningitis (VM), and 9.7% tubercular meningitis (TBM), with 26.4% controls. Organisms were isolated in 12.5% of the cases by blood culture and 25% of cases through CSF culture. Blood CRP was positive in all groups, with the highest values in PM (53.12 ± 28.88 mg/dl) and PPM (47.55 ± 34.34 mg/dl); this was not statistically significant (P = 0.08). The CSF CRP levels were significantly higher (P <0.001) in PM (45.75 ± 28.50 mg/dl) and PPM (23.11 ± 23.98 mg/dl). The sensitivity and specificity of blood CRP was 90.62%, 88.88%, 64.7%, 70% and 32.4%, 30.97%, 24.52%, 26.12% and that of CSF CRP was 96.87%, 66.66%, 20.58%, 10% and 74.73%, 63.71%, 50.94%, 55.35% for PM, PPM, VM and TBM, respectively. CONCLUSION Because of its high sensitivity, both CSF CRP and blood CRP can be used to screen for bacterial meningitis (both PM and PPM). CSF CRP screening yielded results with a higher specificity than blood CRP; hence, it can be a supportive test along with CSF cytology, biochemistry, and microbiology for diagnosing meningitis.