Clinical Significance of Interleukin-6 in the Diagnosis of Sepsis and Discriminating Sepsis Induced by Gram-negative Bacteria.

BACKGROUND: To discuss the clinical significance of interleukin (IL)-6 in the differential diagnosis of sepsis and its capability of differentiating the sepsis induced by Gram-negative bacteria from that induced by Gram-positive bacteria. METHODS: A total of 379 children with sepsis were involved in this study to form the case group, and their C-reactive protein (CRP), procalcitonin (PCT) and IL-6 levels before antibiotics and after recovery were checked. Receiver operating characteristic curve was applied to evaluate the significance of CRP, PCT and IL-6 in the differential diagnosis of sepsis and their capability of differentiating the sepsis induced by Gram-negative bacteria from that induced by Gram-positive bacteria. RESULTS: When these 3 indicators were applied to the differential diagnosis of sepsis, the area under the curve (AUC) of IL-6, PCT and CRP was 0.881, 0.877 and 0.754, respectively. The combination of IL-6 and PCT presented highest diagnostic efficiency. CRP, PCT and IL-6 levels in children with sepsis induced by Gram-negative bacteria were significantly higher than those in children with sepsis induced by Gram-positive bacteria. CONCLUSIONS: CRP, IL-6 and PCT are applicable to the differential diagnosis of sepsis and differentiating the sepsis induced by Gram-negative bacteria from Gram-positive bacteria. Appropriate combinations of these indicators are capable of increasing differential diagnosis efficiency. These indicators can be used as markers of antibiotics usage, but whether they can be used as markers to withdraw antibiotics is still needed to be observed.

Utility of cytokines to predict neonatal sepsis.

BACKGROUND: Sepsis is an important cause of neonatal morbidity and mortality worldwide. Diagnosis and treatment of neonatal sepsis relies on clinical judgment and interpretation of nonspecific laboratory tests. In a prospective cohort, we measured inflammatory cytokines as a potential biomarker for neonatal sepsis. METHODS: Serum inflammatory cytokine levels were evaluated in the early stage of neonatal sepsis and after antimicrobial treatment. Receiver operating characteristic curves assessed the diagnostic value of cytokines. We performed multiple logistic regression analysis to characterize the role of each cytokine independently for infants with culture proven sepsis. RESULTS: C-reactive protein, interleukin (IL)-6, IL-10 and IL-6/IL-10 levels were significantly elevated in neonatal sepsis when compared with the control group and there were 1.4 (95% confidence interval (CI): 1.2-1.5), 4.9 (95% CI: 4.6-5.1), 5.1 (95% CI: 4.5-5.6), and 10.2 (95% CI: 9.2-11.1) fold greater odds, respectively, to predict neonatal sepsis when increased. After effective treatment, median IL-6 (pretreatment value: 263.0 pg/ml and post-treatment value: 7.4 pg/ml) and IL-6/IL-10 levels (pretreatment value: 16.6 and post-treatment value: 1.4) significantly decreased. The areas under the curve for IL-6, IL-10, IL-6/IL-10 and C-reactive protein for differential diagnosis were 0.98, 0.82, 0.90, and 0.88, respectively. CONCLUSION: IL-6 and IL-6/IL-10 outperformed C-reactive protein to diagnose neonatal sepsis. Of the cytokines studied, IL-6 was the most sensitive, whereas IL-6/IL-10 was the most specific predictor of neonatal sepsis.

Clinical Value of Assessing Cytokine Levels for the Differential Diagnosis of Bacterial Meningitis in a Pediatric Population.

We performed a prospective observational study to evaluate the utility of measuring inflammatory cytokine levels to discriminate bacterial meningitis from similar common pediatric diseases. Inflammatory cytokine levels and other cerebrospinal fluid (CSF) physicochemical indicators were evaluated in 140 patients who were diagnosed with bacterial meningitis via microbiological culture or PCR assay. The CSF concentrations of interleukin (IL)-6 and IL-10, CSF/blood IL-6 and IL-10 ratios, CSF white blood cell count, and CSF micro total protein were significantly elevated in bacterial meningitis patients compared with healthy children or patients with viral encephalitis, epilepsy, or febrile convulsions (P < 0.001). The area under the curve values for CSF concentrations of IL-6 and IL-10, CSF/blood IL-6 and IL-10 ratios, CSF white blood cell count, and CSF micro total protein to identify bacterial meningitis episodes by receiver-operating characteristic analysis were 0.988, 0.949, 0.995, 0.924, 0.945, and 0.928, respectively. The area under the curve for the combination of CSF IL-6 and CSF/blood IL-6 ratio was larger than that for either parameter alone, and the combination exhibited enhanced specificity and positive predictive value. After effective meningitis treatment, CSF IL-6 levels dropped significantly. These results suggest that CSF IL-6 and CSF/blood IL-6 ratio are good biomarkers in discriminating bacterial meningitis. Evaluating CSF IL-6 and CSF/blood IL-6 ratio in combination can improve diagnostic efficiency. Additionally, CSF IL-6 levels can be used to monitor the effects of bacterial meningitis treatment.