{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,24]],"date-time":"2026-08-24T10:33:43Z","timestamp":1787567623646,"version":"build-2736575974"},"reference-count":13,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2026,8,24]],"date-time":"2026-08-24T00:00:00Z","timestamp":1787529600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"region Bourgogne Franche-Comt\u00e9","award":["APIRBFC 2016"],"award-info":[{"award-number":["APIRBFC 2016"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>Background\/Objectives: Early feeding intolerance (FI) affects 20\u201350% of critically ill patients receiving enteral nutrition, yet no validated predictive tool exists and diagnosis remains retrospective. Plasma citrulline, mainly synthesized by enterocytes, is considered as the \u201cfactor V of the intestine\u201d. The citrulline generation test (CGT) evaluates small bowel mucosal function by measuring the increase in plasma citrulline after glutamine administration. We hypothesized that patients with a lower CGT would be more prone to FI. We aimed to compare CGT results according to the presence or absence of FI and to identify factors associated with CGT. Methods: This prospective study was conducted in the medical intensive care unit (ICU) of Besancon Hospital. Plasma citrulline and glutamine concentrations were measured at admission and after an alanine\u2013glutamine dipeptide bolus. CGT was defined as the slope between basal and 90 min peak plasma citrulline concentrations. Signs of FI were collected during follow-up. Results: Among the sixty-six included patients, nine (14%) developed FI by day three, only characterized by vomiting and gastric residual volumes above 500 mL; abdominal pain or diarrhea were not observed. CGT values did not differ between patients with and without FI. CGT correlated positively with baseline citrulline and peak glutamine concentrations. Conclusions: FI was not associated with CGT, possibly because FI was predominantly gastric rather than intestinal. Low CGT values were associated with low plasma citrulline concentrations, suggesting reduced functional enterocyte mass. The positive correlation between CGT and peak plasma glutamine suggests that CGT not only reflects enterocyte function but also glutamine bioavailability.<\/jats:p>","DOI":"10.3390\/nu18172759","type":"journal-article","created":{"date-parts":[[2026,8,24]],"date-time":"2026-08-24T09:20:02Z","timestamp":1787563202000},"page":"2759","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Feeding Intolerance and Citrulline Generation Test in the Critically Ill: A Prospective Study"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0009-0000-0536-6421","authenticated-orcid":false,"given":"Chlo\u00e9","family":"Hild","sequence":"first","affiliation":[{"name":"Universit\u00e9 Marie et Louis Pasteur, CHU Besan\u00e7on, SINERGIES, 25000 Besan\u00e7on, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4838-0113","authenticated-orcid":false,"given":"Thibault","family":"Vieille","sequence":"additional","affiliation":[{"name":"Medical Intensive Care Unit, Besan\u00e7on University Hospital, 25030 Besan\u00e7on, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-0405-0820","authenticated-orcid":false,"given":"Marc","family":"Puyraveau","sequence":"additional","affiliation":[{"name":"Clinical Methodology Unit, Besan\u00e7on University Hospital, 25030 Besan\u00e7on, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3728-2334","authenticated-orcid":false,"given":"Hadrien","family":"Winiszewski","sequence":"additional","affiliation":[{"name":"Universit\u00e9 Marie et Louis Pasteur, CHU Besan\u00e7on, SINERGIES, 25000 Besan\u00e7on, France"},{"name":"Medical Intensive Care Unit, Besan\u00e7on University Hospital, 25030 Besan\u00e7on, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Karena Moretto","family":"Riedweg","sequence":"additional","affiliation":[{"name":"Biochemistry Unit, Besan\u00e7on University Hospital, 25030 Besan\u00e7on, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7092-9323","authenticated-orcid":false,"given":"Ga\u00ebl","family":"Piton","sequence":"additional","affiliation":[{"name":"Universit\u00e9 Marie et Louis Pasteur, CHU Besan\u00e7on, SINERGIES, 25000 Besan\u00e7on, France"},{"name":"Medical Intensive Care Unit, Besan\u00e7on University Hospital, 25030 Besan\u00e7on, France"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"99","DOI":"10.1186\/s13613-025-01509-0","article-title":"Expert consensus-based clinical practice guidelines for nutritional support in the intensive care unit: The French Intensive Care Society (SRLF) and the French-Speaking Group of Pediatric Emergency Physicians and Intensivists (GFRUP)","volume":"15","author":"Reignier","year":"2025","journal-title":"Ann. 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Recommendations of the ESICM Working Group on Abdominal Problems","volume":"38","author":"Malbrain","year":"2012","journal-title":"Intensive Care Med."},{"key":"ref_13","first-page":"152","article-title":"Biomarkers of gut barrier failure in the ICU","volume":"22","author":"Piton","year":"2016","journal-title":"Curr. Opin. Crit. Care"}],"container-title":["Nutrients"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-6643\/18\/17\/2759\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,24]],"date-time":"2026-08-24T09:29:20Z","timestamp":1787563760000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-6643\/18\/17\/2759"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,8,24]]},"references-count":13,"journal-issue":{"issue":"17","published-online":{"date-parts":[[2026,9]]}},"alternative-id":["nu18172759"],"URL":"https:\/\/doi.org\/10.3390\/nu18172759","relation":{},"ISSN":["2072-6643"],"issn-type":[{"value":"2072-6643","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,8,24]]}}}