Quantification of fatty acid ethyl esters (FAEE) and ethyl glucuronide (EtG) in meconium from newborns for detection of alcohol abuse in a maternal health evaluation study

Abstract

Fatty acid ethyl esters (FAEE) and ethyl glucuronide (EtG) were determined in 602 meconium samples in a maternal health evaluation study for detection of gestational alcohol consumption. A validated headspace solid phase microextraction method in combination with GC-MS was used for FAEE and the cumulative concentration of ethyl palmitate, ethyl linoleate, ethyl oleate, and ethyl stearate with a cut-off of 500 ng/g was applied for interpretation. A new and simple method was developed and validated for quantification of EtG from 10-20 mg meconium with D(5)-EtG as internal standard consisting of 30 min. extraction with methanol/water (1:1, v/v), evaporation of methanol, filtration of the aqueous solution through a cellulose filter and injection into LC-MS-MS. The limits of detection and quantification for EtG were 10 and 30 ng/g, the recovery 86.6 to 106.4% and the standard deviation of the concentrations ranged from 13% at 37 ng/g to 5% at 46,700 ng/g (N = 6). FAEE above the cut-off were found in 43 cases (7.1%) with cumulative concentrations between 507 and 22,580 ng/g and with one outlier of about 150,000 ng/g (EtG not detected). EtG was detected in 97 cases (16.3%) and concentrations between LOD and 10,200 ng/g with another outlier of 82,000 ng/g (FAEE 10,500 ng/g). Optimal agreement between the two markers was obtained with a cut-off for EtG of 274 ng/g and 547 cases with both FAEE- and EtG-negative, 33 cases with both FAEE- and EtG-positive, nine cases with FAEE-positive and EtG-negative, and seven cases with FAEE-negative and EtG-positive. Differences in physical, chemical, and biochemical properties and in the pharmacokinetic behavior are discussed as reasons for the deviating cases. In none of the 602 cases, serious alcohol consumption was reported by the mothers and no evidence for gestational ethanol exposure was observed in the medical investigation of the newborns. It is concluded that the combined use of FAEE and EtG in meconium as markers for fetal alcohol exposure essentially increases the accuracy of the interpretation and helps to avoid false positive and false-negative results.

Trastornos del espectro alcohólico fetal. Biomarcadores del consumo de etanol durante la gestación.

“…Los siguientes FAEEs (E16:0, E18:0, E18:2, E18:3, E20:4) se han sugerido como biomarcadores de meconio (26,27). La suma de estos FAEEs con un punto de corte de 2 nmol/g o 50 ng/g de meconio se recomendó como prueba de screening para el consumo de alcohol con una sensibilidad del 100 % y una especifi cidad del 98,4 % usando la suma al menos de cuatro FAEEs individuales (palmitato de etilo, estearato, oleato y linoleato) para la detección de consumo excesivo de alcohol (25,28).…”

Exposição pré-natal ao etanol: toxicidade, biomarcadores e métodos de detecção

“…Observando a tabela 1, verifica-se que o estudo que apresentou limite de detecção (LDD) mais baixo foi o de Garcia-Algar et al 39 , que utilizou CL/EM em tandem (considerando a relação 2 nmol/g ≅ 600 ng/g, conforme Bakdash et al 1 ). Entretanto, todos os LDD e limites de quantificação (LDQ) apresentados foram adequados.…”

“…Foi recentemente proposto ser um marcador de exposição alcoólica intrauterina em dois estudos 1,42 . Os autores detectaram EtG em 155 amostras de mecônio de um total de 177, com concentrações entre 5 e 6.300 ng/g.…”

“…EtG foi detectado em 16,3% de amostras de mecônio num estudo feito com 602 amostras 1 . Os autores compararam os resultados de EtG com os obtidos para EEAG, que foi encontrado em concentração acima do cutoff em 7,1% das amostras.…”

“…O consumo excessivo de álcool durante a gravidez é perigoso ao feto, podendo levar ao nascimento prematuro, retardo físico e do desenvolvimento mental e até à morte do neonato 1 . A intervenção farmacológica e educacional da criança exposta ao etanol in utero pode ser mais eficiente se for possível a identificação precoce da exposição 2 .…”