Plasma citrulline after small bowel transplantation: effect of time from transplantation, acute cellular rejection, and renal failure

Background Plasma citrulline concentration (CIT) depends on its synthesis by enterocytes and its catabolism by renal tubules. To evaluate CIT applicability as a marker of acute cellular rejection (ACR) after intestinal transplantation (ITx), CIT was investigated according to time from ITx, episodes of ACR, and creatinine clearance (CrCl). Methods Twenty‐four adult ITx recipients were prospectively studied. The results were compared with those of 19 healthy controls (HCs) and of 29 patients with chronic renal failure (CRF). Results In ITx recipients, CIT was lower than in HCs during the first two postoperative weeks; it then progressively increased and reached the range observed in HCs, approximately between the 31st and the 45th postoperative day. A positive association with postoperative days (R = 0.63; p