Interleukin 35: A novel candidate biomarker to diagnose early onset sepsis in neonates.

BACKGROUND

Early onset sepsis (EOS) remains a major cause of morbidity and mortality in newborns; however, current diagnostic tools are inadequate. We evaluated the accuracy of a novel cytokine, interleukin (IL)-35, for the diagnosis of EOS in comparison with other infection markers.

METHODS

One hundred fifty-seven neonates with suspected sepsis in the first 3days of life were enrolled in this perspective study. All enrolled patients were divided into infected group and unlikely infected group according to clinical data. IL-35, C-reactive protein (CRP), procalcitonin (PCT), white blood cell (WBC) count, and blood culture were measured once the suspected EOS was documented.

RESULTS

Serum concentration of IL-35 was increased significantly in the infected group compared with the unlikely infected group (median 36.4 versus 27.1pg/ml, respectively, p<0.001). The area under receiver-operating characteristic (ROC) curve were 0.756 for IL-35, 0.713 for PCT (age-adjusted), 0.670 for CRP, and 0.619 for WBC. With a cut-off value of 31.7pg/ml, the diagnostic sensitivity and specificity of IL-35 were 78.48% and 66.67%, respectively. Moreover, unlike PCT concentration, IL-35 concentration did not fluctuate in neonates who were unlikely to be infected (p=0.885).

CONCLUSION

The diagnostic performance of IL-35 was superior to that of PCT and other commonly used markers, suggesting that IL-35 may be a valuable tool for EOS diagnosis.