Evaluation of high sensitivity C-reactive protein assay in cerebrospinal fluid on the Dimension RxL analyzer

Low sensitivity and specificity in traditional laboratory tests became insufficient for accurate diagnostics and initiation of proper treatment of patients infected with bacterial meningitis. High sensitivity Creactive protein (hsCRP) may be an appropriate supplement for rapid diagnosis of bacterial meningitis. The subject of our investigation was the determination of C- reactive protein in cerebrospinal fluid (CSF) during acute bacterial meningitis. Methods: HsCRP was analysed by a sensitive immunoturbidimetric assay using the Dimension RxL analyser (Siemens). Cerebrospinal fluid concentrations of C-reactive protein have been measured in 20 patients (age range,1 to 50 years) presenting with acute bacterial meningitis and also in a non-infected, non-inflamed control group (n=25). Results: The accuracy and precision of the method proved to be satisfactory. Repeatability of serial sampling for hsCRP described by coefficient of variation were CV=2.1-4.5%. This assay hsCRP in cerebrospinal fluid demonstrates adequate performance characteristics for routine clinical use. Elevated levels of CRP were found in 95% patients with bacterial meningitis. The mean CRP value in 25 uninfected control group was 0.25 mg/L (range 0.10-0.55). The mean CRP for patients with bacterial meningitis was 21.4 mg/L (range 0.40-100). Conclusions: A sensitive assay for CRP in CSF would be an useful adjunct to conventional investigation of acute infective meningitis.