In polytrauma intensive care unit (ICU) patients, glutamine (GLN) become a "conditionally essential" amino acid; its role has been extensively studied in numerous clinical trials but their results are inconclusive. We evaluated the IgA–mediated humoral immunity after GLN supplementation in polytrauma ICU patients.
All consecutive patients with polytrauma who required mechanical ventilation and enteral nutrition (EN) provided within 24 hours since the admission in ICU at the University Hospital of Foggia from September 2016 to February 2017 were included. Thereafter, two groups were identified: patients treated by conventional EN (25 kcal/kg/die) and patients who have received conventional EN enriched with 50 mg/kg/ideal body weight of alanyl-GLN 20% intravenously. We analyzed plasmatic concentration of IgA, CD3+/CD4+ T Helper Lymphocytes, CD3+/CD8+ T suppressor Lymphocytes, CD3+/CD19+ B Lymphocytes, IL-4 and IL-2 at admission, at 4, 8 days. We identified 30 patients, with 15 subjects per group. IgA levels increased significantly in GLN vs control group at T0, T4 and T8.CD3+/CD4+ T helper lymphocytes and CD3+/CD8+ T suppressor lymphocytes levels significantly increased in GLN vs control group at T4 and T8. CD3+/CD19+ B lymphocytes levels increased significantly in GLN vs control group only at T8.IL-2 and IL-4 levels showed no significant differences when comparing GLN with control group.
Our study showed that there was an improvement in humoral and cell-mediated immunity with GLN supplementation in polytrauma ICU patients using recommended doses.