Glutamine alimentation in catabolic state

Glutamine should be reclassified as a conditionally essential amino acid in the catabolic state because the body's glutamine expenditures exceed synth esis and low glutamine levels in plasma are associated with poor clinical o utcome. After severe stress, several amino acids are mobilized from muscle tissue to supply energy and substrate to the host. Glutamine is one of the most important amino acids that provide this function. Glutamine acts as th e preferred respiratory fuel for lymphocytes, hepatocytes and intestinal mu cosal cells and is metabolized in the gut to citrulline, ammonium and other amino acids. Low concentrations of glutamine in plasma reflect reduced sto res in muscle and this reduced availability of glutamine in the catabolic s tate seems to correlate with increased morbidity and mortality. Adding glut amine to the nutrition of clinical patients, enterally or parenterally, may reduce morbidity. Several excellent clinical trials have been performed to prove efficacy and feasibility of the use of glutamine supplementation in parenteral and enteral nutrition. The increased intake of glutamine has res ulted in lower septic morbidity in certain critically ill patient populatio ns. This review will focus on the efficacy and the importance of glutamine supplementation in diverse catabolic states.