Procalcitonin as a Predictive Marker for Bacteremia in Children With a Central Line and Fever.

Abstract

Unnecessary use of antibiotics is an increasing problem. In this study, we sought to determine the diagnostic accuracy of procalcitonin in predicting bacteremia in children with a central line and fever, and we sought to determine optimal cutoff values to maximize sensitivity and specificity. This is the largest study to date in which procalcitonin is examined as a predictive marker of bacteremia in pediatric patients with a central line and fever. We conducted a retrospective cohort study of children aged 0 to 23 years with a central line and fever of 38°C who had procalcitonin and blood cultures drawn before initiation of antibiotics and had no other identified bacterial infection. Patients were also prospectively monitored via a custom-built electronic medical record dashboard for eligibility. There were 523 patients and >2500 procalcitonin values reviewed for eligibility. Of these, 169 (47%) patients and 335 blood cultures with procalcitonin were included. There were 94 (28%) positive bacterial blood cultures and 241 (72%) negative bacterial blood cultures. In bacteremic cultures, the mean procalcitonin level was 9.96 ± 15.96 ng/mL, and the median procalcitonin level was 4.85 ng/mL (interquartile range 18.5). In nonbacteremic cultures, the mean procalcitonin level was 1.23 ± 10.37 ng/mL, and the median procalcitonin level was 0.3 ng/mL (interquartile range 0.7). A receiver operating characteristic analysis indicated a procalcitonin level of ≥0.6 ng/mL as the best cutoff point that produced a sensitivity of 85.6% and a specificity of 65.7% (area under the curve 0.85). Procalcitonin is a sensitive biomarker in predicting bacteremia in children with a central line and fever.