177 Differentiation-Dependant Sensitivity Of Neuronal Precursor Cells Towards Oxidative Stress

Abstract

Background: Fungal Colonization (FC), mostly by Candida spp., and subsequent invasive fungal infection are increasingly frequent features in preterm neonates in NICUs, and several risk factors have been found associated to them. The objective of this study was to evaluate the role of Early-Onset Neutropenia (EON) in the development of FC in preterm very low birth weight (VLBW) neonates in NICU.Methods:Medical records of all Ͻ1500 g birth weight neonates admitted to our 3rd level Facility between 1997 and 2003 and survived more than 1 week were reviewed. Neonates with baseline fungal colonization were excluded, thus final number of considered neonates was nϭ424. For all neonates we recorded: a) the presence of neutropenia in the first week of life (EON), diagnosed with Manroe (J Pediatr 1979) and Mouzinho (Pediatrics 1994) reference values (nϭ52, 12.2%); b) the presence of FC (at least one site), the number and the type of sites colonized during the first month of life. In 25 on 52 neutropenic infants, a 3-days course of Filgrastim (10 mg/kg/die) was performed during the 1st week of life with normalization of the neutrophil count always before the 8th day of life. In neutropenic not treated neonates neutrophil count became spontaneously normal before the beginning of 3rd week of life. Statistical analysis was performed by Chi-square, ANOVA and T-test using SPSS 8.0 for Windows.Results: Statistical analysis did not show significant differences between neutropenic and not neutropenic neonates as for mean gestational age and birth weight, sex, race, outcome and presence of the most common risk factors associated with FC. Incidence of FC in the 2nd, 3rd and 4th week of life was significantly higher in neutropenic (nϭ32/52, 61.5%) than in not neutropenic patients (nϭ134/372, 36%) (Chi-square 14.288, OR 0.32; pϽ0.001). Intensity (as number of different sites affected) and severity (as number of risk sites affected) of FC were as well higher in the neutropenic patients (pϽ0.002 and pϽ0.001 respectively). Treatment with Filgrastim did not change the relative risk for colonization: FC was present in 60% of neutropenic treated neonates and 64% of not treated (pϽ0.28, NS).Conclusion: EON in VLBW neonates significantly influences the rate of colonization by fungal spp. in the first month of life, causing a higher risk that cannot be corrected by filgrastim therapy. VLBW neonates with EON should be carefully monitored for fungal colonization during their stay in NICU, and should undergo prophylactic measures to prevent it. M Marcinkowski, C Buehrer, M Toennessen, B Gerstner, A Gratopp, M Obladen Charité-Campus Virchow-Klinikum, Otto-Heubner-Center for Pediatric and Adolescent Medicine , Department of Neonatology, Berlin, Germany Background: Apoptosis is an endogenous cell suicide mechanism triggered in response to biological factors and genotoxic stimuli often resulting from oxidative stress. Neuronal apoptosis especially in the developing brain may cause long-term brain dysfunction. Cognitve deficits in the later childhoo...