Interleukin-6 serum level assessment using a new qualitative point-of-care test in sepsis: A comparison with ELISA measurements

Objectives: Interleukin-6 (IL-6) is involved in inflammatory diseases, provides prognostical information, and allows the early identification and monitoring of septic patients. We investigated whether IL-6 can be assessed using a new densitometric point-of-care (POC) bedside assay. Design and methods: 392 samples were prospectively collected from 57 intensive care unit patients (38 male, age: 45.2 +/- 16.9years, APACHE II score: 25.4 +/- 4.8). Blinded IL-6 measurements were performed using conventional semiautomatic enzyme-linked immunosorbent assays (ELISA) and the POC test. Results: Mean IL-6 levels were 102.9 +/- 388.6pg/mL (ELISA) and 97.0 +/- 535.5 (POC), A significant correlation was found (P < 0.0001, 0.92). The sensitivity/specificity for sepsis was 82.6%/86.5% (ELISA, AUC: 0.881), and 76.4%/95.0% (POC, AUC: 0.868). Conclusions: Here we demonstrate significant correlations of IL-6 levels determined using a POC test and semiautomatic ELISA. ROC analyses revealed no significant differences between the two tests. With a turn-around time of 20min, the bedside IL-6 test is a new tool that may help to initiate early goal-directed therapy. (C) 2008 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.