Enteral Nutrition Supplemented with l-glutamine in Patients with Sepsis

Abstract

Objective: To evaluate the effect of enteral nutrition (EN) supplemented with L-glutamine in patients with sepsis. Methods: Thirty patients received EN. Fifteen patients received EN supplemented with glutamine (30 g; GLN group) for 2 d followed by EN supplemented with calcium caseinate (30 g, CAS group), also over 2 d. The other 15 patients received EN with calcium caseinate (30 g; CAS group) for 2 d followed by EN with glutamine (30 g; GLN group), also over 2 days. One washout day with only EN was provided between every 2-d period of EN plus supplementation to all patients. Blood samples were taken before and after supplementation. Results: There were no changes in glycolytic parameters in either group. Leukocytes decreased in the two groups (from 13 650 to 11 500 in the CAS group, p = 0.019; from 12.850 to 11.000 in the GLN group, p = 0.046). Lymphocytes increased in the GLN group (from 954 to 1916, p < 0.0001) and were more numerous after glutamine supplementation (from 1916 to 1085, p < 0.0001, GLN versus CAS). Glutathione plasma concentrations did not differ significantly between the groups. No significant changes were observed in the plasma glutamine and glutamate concentrations. Conclusions: The utilization of glutamine glutamine, despite being supplied enterally, increased the percentage of lymphocytes, indicating that the amino acid was not retained by the enterocytes. The finding of an increased percentage and total number of lymphocytes, indicates significant improvement of the immune system. Considering the observed benefits and the absence of adverse effects, enteral and parenteral diets enriched with L-glutamine or L-alanyl-glutamine are currently recommended for severe ICU patients in order to modulate the immune system.