The effect of parenteral glutamine supplementation on the immune system and nitrogen balance in critically ill patients receiving glutamine enriched enteral nutrition

Aim: Dietary glutamine is mostly utilized by enterocytes and gut associated lymphoid tissue. Glutamine is also an essential amino acid for the rest of the lymphoid cells. We aimed to investigate the effects of the addition of parenteral glutamine to enteral glutamine on lymphocyte subpopulations and nitrogen balance. Materials and Methods: 33 patients (24 M, 9 F; aged 19-76) formed the two groups. Daily energy requirements were measured by indirect calorimetry for 4 days and the amount of glutamine enriched enteral nutrition was adjusted accordingly. In IV-GLN group (n=18) 0.3 g/kg/day parenteral L-alanyl-L-glutamine solution was infused within 6 hours. In the IV-STD group (n=15) isonitrogenous standard amino acid solution was administered. 24 hour urine samples were collected and the nitrogen balance was calculated daily. Blood samples were obtained for lymphocyte subpopulations (CD3, CD4, CD8, CD19, NK, active T cell, IL-4 and IFN-gamma) at the beginning and after 96 hours of supplementation. Results: Demographic variables and APACHE II scores were similar between the groups. There were no significant differences between the groups in terms of lymphocyte subpopulations and cumulative nitrogen balance. Conclusion: In our study, the addition of L-alanyl-L-glutamine or standard amino acid solution parenterally to glutamine enriched enteral nutrition had similar effects in terms of lymphocyte subpopulations and nitrogen balance. This is one of the limited number of studies investigating the effects of the addition of parenteral glutamine to enteral glutamine. Optimal dose and route of glutamine supplemantation for ICU patients still needs to be clarified. Amaç: Diyetle alınan glutaminin çoğu enterositler ve barsakla ilişkili lenfoid doku tarafından kullanılır. Glutamin vücuttaki diğer lenfoid hücreler için de gerekli bir amino asittir. Bu çalışmada enteral glutamine parenteral glutamin eklenmesinin lenfosit alt grupları ve azot dengesi üzerindeki etkilerinin araştırılması amaçlanmıştır. Gereç ve Yöntem: 33 hasta (24 erkek, 9 kadın; 19-76 yaş) iki grubu oluşturdu. Günlük enerji gereksinimleri 4 gün boyunca indirekt kalorimetre ile ölçüldü ve glutaminden zengin enteral nütrisyon solüsyonu miktarı belirlendi. IV-GLN grubunda (n=18) 0.3 g/kg/gün parenteral L-alanyl-L-glutamin solüsyonu 6 saatte infüze edildi. IV-STD grubunda (n=15) izonitrojen standart amino asit solüsyonu verildi. 24 saatlik idrar örnekleri toplanarak günlük azot dengeleri hesaplandı. Lenfosit