Abstract 114

The HLA-DR expression on peripheral blood monocytes has been reported extremely low in adult septic patients. This study was scheduled in order to investigate whether a similar phenomenon occurs during neonatal infections. Twenty two neonates, admitted to the NICU during the first 48 hours of life(gestation age 31+/- 2 weeks), were studied. HLA-DR expression was studied on admission, during infection and at recovery. The expression (%) of HLA-DR on monocytes and its mean fluorescence intensity (MF) were measured by flow cytometry. Statistical analysis of the results was performed by the use of simple factorial ANOVA considering as independent variable the severity of infection (mild or severe) when occurring, and as confounding factors the kind of delivery, gestation age, sex and birth weight. It was found: a) On admission HLA-DR-MF was significantly decreased in neonates with perinatal infection compared to healthy ones, b) The percentage of HLA-DR of monocyte during the course of mild infections showed a significant rise while during severe ones showed a significant drop followed by a significant rise at recovery. In conclusion premature neonates presented remarkable changes on their monocytes HLA-DR during infective illness which could be used as diagnostic and prognostic markers.