Egypt J Pediatr Allergy Immunol, (April 2010), Volume No. 8, Issue 01  
Egypt J Pediatr Allergy Immunol 2010 ; 8 ( 01 ) : 19-25 -
, ESP - 47  
Neutrophil CD64 in early-onset neonatal sepsis
Abdel-Azeem M. El-Mazary   Mohamed F. Afifi   Sheren E. Maher   Mohamed I.Bassyouni      
Background: Neonatal sepsis is a life threatening disease with an incidence of 3.5 to 8 cases per 1,000 live births; and mortality rate 16 to 30%. Cytokines, produced by monocytes, macrophages, and endothelial cells in response to infectious stimuli are important proinflammatory mediators in the early phases of the sepsis syndrome. Elevated serum levels of interleukin-6 (IL-6) had been found in both neonatal and adult sepsis. However, for neonatal sepsis, little is known about a group of molecules playing a central role in the innate immune system. Among them is the neutrophil CD64 which is expressed on neutrophil surface in many inflammatory conditions. Objective: To study the neutrophil CD64 expression in neonates with early onset sepsis and its relation to other laboratory markers as IL6, CRP, total leucocytic count and platelet count. Methods: This study comprised 30 neonates with a gestational age of 28 to 40 weeks with a picture of early onset neonatal sepsis within 48 hours of life admitted to neonatal care unit, Suzan Mubarak Hospital, El-Minia University, Egypt during the period from February, 2008 to January, 2009 and 20 healthy neonates age and sex matched as a control group. Neutrophil surface expression of CD64 was quantified with flow cytometry. We measured plasma IL6, C-reactive protein, complete blood count and blood culture. Results: Neutrophil CD64 expression was increased significantly in neonates with neonatal sepsis than controls (p=0.001). Cases with history of premature rupture of membranes (PROM) ?48 hours, with positive blood culture or poor outcome had the highest levels of neutrophil CD64 expression (52850.7, 55858.4 and 560.943.9 relative fluorescence units (RFU) respectively). A significant positive correlation was found between CD64 levels and the levels of IL6 (r=0.71, p=0.001),C-reactive protein (r=0.74, p=0.001) and total leucocytic count (r=0.76 ,p=0.01) and negative correlation with gestational age (r=-0.92, p=0.001) and body weight (r=- 0.92, p=0.006), but there was no correlation between it and platelet count (r=-0.32, p=0.08). Conclusion: Neutrophil CD64 expression is increased in neonates with early-onset neonatal sepsis and correlated well with other laboratory markers of sepsis.