Ethanolaminuria: a non-specific laboratory finding in the seriously ill infant

Ethanolamine is a compound that is frequently seen in urinary amino acid analysis. Although there is a single report of increased ethanolamine excretion associated with a distinctive storage disease in two siblings, the significance of ethanolaminuria is not known. We measured urinary ethanolamine/creatinine ratios in 102 hospitalized infants under two years of age and examined the clinical correlations in six cases whose ratios were more than five-fold higher than the maximum value for the established reference range. We found that ethanolamine excretion was strongly dependent on age even when the data were corrected for significant positive skewing. Increased ethanolamine excretion was common in the first week of life, but five of the six cases we specifically studied were characterized by progressive, debilitating illness and three of the six patients subsequently died. Although we found no evidence of a storage disorder, we did note that there was evidence of neuronal white matter degeneration in most but not all cases. Thus, ethanolaminuria appears to be a non-specific sign of severe neurological disease rather than a distinctive feature of a specific inborn error of metabolism.