Evaluation of IL-8-concentrations in plasma and lysed EDTA-blood in healthy neonates and those with suspected early onset bacterial infection.
Plasma IL-8 is a diagnostic parameter of early-onset bacterial infection (EOBI) in neonates but has a short half-life. The detergent-lysed whole-blood (DLWB) IL-8 consists of both extracellular and cell-bound IL-8. The objective of this study was to investigate kinetics of plasma and DLWB IL-8 in healthy newborns and those with suspected EOBI and to test the hypothesis that determination of DLWB IL-8 results in higher sensitivity for EOBI detection. Sixty-one neonates with clinical and serologic signs of EOBI composed the study group; 188 neonates with risk factors but without EOBI served as control subjects. IL-8 concentrations were determined in plasma and DLWB. In the control group, DLWB IL-8 concentrations were 280-fold higher (9599 pg/mL; SD 4433) up to 24 h post partum than corresponding plasma levels (34.2 pg/mL; SD 18.1). The sensitivity of DLWB versus plasma IL-8 for EOBI was 0.97 versus 0.71 after 6 h and 0.70 versus 0.32 after 24 h. Corresponding values for specificity were 0.95 versus 0.90 after 6 h and 0.92 versus 0.99 after 24 h. After 24 h, the negative predictive value for DLWB versus plasma IL-8 was 0.80 versus 0.66. DLWB IL-8 showed a higher sensitivity for EOBI within 6 h after first clinical suspicion than plasma IL-8. It also remained elevated longer. Our results suggest that DLWB IL-8 results in a higher sensitivity for EOBI.
Orlikowsky
Thorsten W
TW
Univ.-Kinderklinik Tübingen, Calwerstrasse 7, 72076 Tübingen, Germany. thorsten.orlikowsky@med.uni-tuebingen.de
Neunhoeffer
Felix
F
Goelz
Rangmar
R
Eichner
Martin
M
Henkel
Christine
C
Zwirner
Manfred
M
Poets
Christian F
CF
D017668:Age of Onset; D000925:Anticoagulants; D001424:Bacterial Infections / Q000097:blood* / Q000175:diagnosis*; D015415:Biomarkers / Q000097:blood; D002624:Chemistry, Clinical / Q000379:methods* / Q000592:standards; D003902:Detergents; D004492:Edetic Acid; D006801:Humans; D007231:Infant, Newborn; D016209:Interleukin-8 / Q000097:blood*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
D000925:Anticoagulants; D015415:Biomarkers; D003902:Detergents; D016209:Interleukin-8; D004492:Edetic Acid