Diagnostic Accuracy of Clinical Signs and Biochemical Parameters for External Ventricular CSF Catheter-Associated Infection.

Background and Objectives: Few prospective well-designed diagnostic accuracy studies have been performed to study the parameters of infection in patients suspected for external ventricular catheter-associated infection. Our objective was to analyze the diagnostic accuracy of clinical characteristics and biochemical and microbiological parameters in diagnosing external ventricular CSF catheter-associated infection. Methods: From 2014 to 2017, we performed a single-center cohort study in consecutive patients at the intensive care unit who required an external ventricular CSF catheter in the Hague, the Netherlands. CSF was sampled and analyzed daily. Ventricular catheter-associated infection was defined according to the 2017 Infectious Diseases Society of America's Clinical Practice Guidelines. We compared clinical characteristics and biochemical parameters between patients with and without infection from 3 days before to 3 days after the day the CSF sample was collected that grew bacteria. Results: A total of 103 patients were included of whom 15 developed a catheter-associated infection (15%). The median day cultures were positive was 3 days after CSF collection (interquartile range [IQR] +2 to +4). On day 0, none of the tests could differentiate between patients with and without infection. The CSF leukocyte count was increased in patients with ventricular catheter-associated infection as compared with patients without on days +2 and +3. The difference was most prominent on day +2 (1,703 × 10 Discussion: An elevated CSF leukocyte count and increased percentage of PMNs are the strongest indicators for external catheter-associated infections on the days before culture positivity. New CSF markers of drain-associated infection should be studied to enable earlier diagnosis and treatment in patients with an infection and reduce antibiotic treatment in those with no infection. Classification of Evidence: This study provides Class I evidence that in individuals requiring an external ventricular CSF catheter, an elevated CSF leukocyte count and an increased percentage of PMNs are the strongest indicators of catheter-associated infections in the days before CSF culture positivity.