Glutamine granule-supplemented enteral nutrition maintains immunological function in severely burned patients

Glutamine is an important energy source for immune cells. It is a necessary nutrient for cell proliferation, and serves as specific fuel for lymphocytes, macrophages, and enterocytes when it is present in appropriate concentrations. The purpose of this clinical study was to observe the effects of enteral nutrition supplemented with glutamine granules on immunologic function in severely burned patients. Forty-eight severely burned patients (total burn surface area 30-75%, full thickness burn area 20-58%) who met the requirements of the protocol joined this double-blind randomized controlled clinical trail. Patients were randomly divided into two groups: burn control group (B group, 23 patients) and glutamine treated group (Gln group, 25 patients). There was isonitrogenous and isocaloric intake in both groups, Gln and B group patents were given glutamine granules or placebo (glycine) at 0.5 g/kgd for 14 days with oral feeding or tube feeding, respectively. The plasma level of glutamine and several indices of immunologic function including lymphocyte transformation ratio, neutrophil phagocytosis index (NPI), CD4/CD8 ratio, the content of immunoglobulin, complement C3, C4 and IL-2 levels were determined. Moreover, wound healing rate of burn area was observed and then hospital stay was recorded. The results showed significantly reduced plasma glutamine and damaged immunological function after severe burn Indices of cellular immunity function were remarkably decreased from normal controls. After taking glutamine granules for 14 days, plasma glutamine concentration was significantly higher in Gln group than that in B group (607.86+/-147.25 micromol/L versus 447.63+/-132.38 micromol/L, P<0.01). On the other hand, cellular immunity functions were improved in Gln group, such as lymphocyte transformation ratio, NPI, CD4/CD8 ratio and IL-2 compared those in the B group (P<0.05-0.01). However, for humoral immunity function such as the concentration of IgG, IgM, C3, C4, no marked changes were seen compared with the B group (P>0.05). In addition, wound healing was better and hospital stay days were reduced in Gln group (46.59+/-12.98 days versus 55.68+/-17.36 days, P<0.05). These indicated that immunological function damage is present after severe burn; supplemented glutamine granules with oral feeding or tube feeding abate the degree of immunosuppression, improve immunological function especially cellular immunity function, ameliorate wound healing and reduce hospital stay.