The Role of Neutrophil CD11b Compared to Neutrophil CD64 as an Early Diagnostic, Monitoring, and Prognostic Sepsis Marker in Neonatal ICUs: Case-Control-Methodological Study.

Early diagnosis and treatment of neonatal sepsis are crucial to cut off its major medical consequences: lifelong morbidities, neurodevelopmental disabilities, and a high number of neonatal mortalities. This study is aimed at determining the diagnostic and prognostic performance of CD11b as a sepsis biomarker for detecting neonatal sepsis at early stages compared to nCD64 and the other conventional sepsis parameters. Two hundred eleven neonates were enrolled from three Egyptian neonatal ICUs (NICUs), and they were classified into two main groups: the control group ( = 101) and the sepsis group ( = 110). Enrolled neonates were subjected to full sepsis screening, including complete blood count (CBC), C-reactive protein (CRP), blood cultures, and flow cytometry analysis for both CD64 and CD11b on the neutrophil surface (results represented as a percentage (percent) and mean fluorescent intensity (MFI) units for either biomarker). nCD64% (median = 44.15%) was significantly enhanced in the sepsis group compared to the controls (median = 25%), achieving 90.8% specificity, 92.8% sensitivity, and AUC = 0.894, respectively. CD64 MFI and CD11b MFI could differentiate between sepsis and control groups but with low undesirable diagnostic performance (sensitivity: 72.5% and 59.1%; specificity: 54.4% and 69.4%; AUC: 0.634 and 0.144, respectively). CD11b% could not discriminate between sepsis and control neonates (sensitivity and specificity of 31.8% and 73.6%, respectively) with an AUC of 0.405. hs-CRP had moderate diagnostic performance, achieving sensitivity and specificity of 69% and 78.15%, respectively, and AUC = 0.586. ROC analysis showed that combined hs-CRP and CD64% results had the highest sensitivity and specificity in the current study, being 93.9% and 97.2%, with AUC = 0.938, respectively. CD64%, CD64 MFI, CD11b MFI, and hs-CRP are increased in neonates with sepsis comparable to the controls. CD64% has a superior diagnostic performance comparable to nCD11b and hs-CRP. Combined nCD64 with hs-CRP measurement can provide rapid and accurate diagnostic modality for sepsis diagnosis in correlation with the patient's clinical condition and context with the results of other hematological indices; neutrophil CD64 can be routinely applicable in NICUs for better sepsis management. It is statistically evident that nCD11b is less ideal compared to nCD64 as a diagnostic, prognostic, or monitoring sepsis marker.