Diagnosis of fetal alcohol spectrum disorders (FASD) is challenging and typically requires confirmation of in utero alcohol exposure. Due to the poor reliability of maternal self-reports, biomarkers have emerged to address the problem of obtaining exposure history. A relatively novel method for detecting prenatal alcohol exposure is analysis of meconium for fatty acid ethyl esters (FAEEs), which are non-oxidative ethanol metabolites. Screening newborns using meconium FAEEs may facilitate early diagnosis and intervention in alcohol-affected individuals. The overall objective of this thesis is to further investigate, validate, and assess the clinical utility of meconium FAEE analysis as a screening tool for the identification of neonates at-risk for FASD. This objective was addressed in four separate studies. The first study assessed whether meconium FAEE concentrations can be predictive of ethanol-induced organ injury in fetal sheep, and determined that the levels of these esters could be used to identify fetuses at-risk for organ dysfunction that do not display overt physical signs of ethanol teratogenicity. The second study investigated the effect of delayed meconium collection and contamination with postnatal stool on FAEE analysis, and determined it to be a risk factor for false positive test results. In the third study, maternal willingness to partake in an open meconium screening program was assessed and found to be low enough to diminish the utility of meconium FAEE testing for population-based open screening. Lastly, a systematic review examining the capacity for FAEE synthesis and the enzymology of this non-oxidative metabolic pathway in mammalian organs and tissues revealed that FAEE synthesis is mediated by numerous enzymes and isoenzymes, many of which have other primary physiological functions, and that their contribution to overall FAEE-synthesis may be tissue-specific. Overall, the results of this research provide new information on the benefits, limitations, and utility of meconium FAEE testing as a screening tool for identifying prenatal alcohol exposure − a test that may be of great clinical value in the diagnosis and management of FASD.
| Identifer | oai:union.ndltd.org:TORONTO/oai:tspace.library.utoronto.ca:1807/43771 |
| Date | 14 January 2014 |
| Creators | Zelner, Irene |
| Contributors | Koren, Gideon |
| Source Sets | University of Toronto |
| Language | en_ca |
| Detected Language | English |
| Type | Thesis |
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