Diagnostic Value of Neutrophil Cd64 in Sepsis Patients in the Intensive Care Unit: A Cross-sectional Study

Abstract Background Sepsis is a major cause of morbidity and mortality in intensive care units (ICUs). The neutrophil CD64 (nCD64) index has been suggested to be a biomarker that can help early diagnose sepsis in these settings. However, little is known about the role of this biomarker in Asian patients. This study examined the cut-off and predictive values of nCD64 for diagnosing sepsis in Vietnamese ICU patients. Methods A cross-sectional study was conducted at the General ICU of Cho Ray Hospital between January 2019 and April 2020. All 104 newly admitted patients with or without sepsis were included. Sensitivity, specificity, positive predictive value, negative predictive value, and receiver operating characteristic (ROC) curves were calculated to compare the diagnostic value of nCD64 with that of serum procalcitonin (PCT) and while blood cell (WBC) count for sepsis. Results The median nCD64 index in sepsis patients was statistically higher than that of non-sepsis patients (3,106 [1,970-5,200] vs 745 [458-906] molecules/cell, P<0.001). ROC analysis found that the area under the ROC curve (AUC) value of nCD64 was 0.92, which was higher than that of PCT (0.872) and WBC (0.637), nCD64 combined with WBC (0.906), and nCD64 combined with WBC and PCT (0.919) but lower than that of nCD64 combined with PCT (0.924). With an AUC value of 0.92, the nCD64 index of 1,311 molecules/cell detected sepsis with a sensitivity of 89.9%, specificity of 85.7%, positive predictive value of 92.5%, and negative predictive value of 81.1%. Conclusions nCD64 can be used as a useful marker for early detecting sepsis in adult ICU patients. A combination of nCD64 and PCT may improve the diagnostic accuracy. More large studies are needed to examine the variance of the cut-off values of nCD64 for diagnosing sepsis in the wider Vietnamese population and comparable countries.