Enterocyte biomarkers and nutrition of the critically ill

Early initiation of nutrition is required among critically ill patients hospitalized in the ICU. Enteral nutrition (EN) is the preferred route when the gut is presumed to be functioning but EN is associated with a risk of digestive intolerance which occurs in one half of the patients and which is associated with a poor prognosis. Evaluation of the small bowel function of critically ill patients hospitalized in the ICU is difficult. Plasma citrulline is a marker of functional enterocyte mass and plasma I-FABP is a marker of enterocyte damage. Plasma citrulline concentration is a validated biomarker of enterocyte mass among patients presenting with short bowel syndrome or with villous atrophy-associated diseases. I-FABP appears to be a promising biomarker of acute mesenteric ischemia. There is evidence that both biomarkers could be of interest among critically ill patients for the identification of small bowel damage or dysfunction. There is a two-way connection between enterocyte biomarkers and the route of nutrition. On the one hand, in the context of short bowel syndrome, plasma citrulline concentration appears to be a promising indicator for the evaluation of the tolerance of the enteral route and the possibility to wean parenteral nutrition. On the other hand, among critically ill patients, there is evidence that the route of nutrition modify the evolution of enterocyte biomarkers. Globally, it seems that, comparatively to PN, EN is associated with a more rapid increase of plasma citrulline concentration. This raises the question of a possible beneficial effect of EN over PN on the trophicity of the small bowel mucosa. (C) 2019 Societe francophone nutrition clinique et metabolisme (SFNCM). Published by Elsevier Masson SAS. All rights reserved.