Clinical evidence for enteral nutritional support with glutamine: a systematic review

The purpose of this systematic review was to locate and assess the quality of scientific evidence to establish a graded recommendation based on the effectiveness of glutamine-enriched enteral nutrition in different medical and surgical conditions. We were concerned with the following topics: 1) benefits of enteral administration of glutamine in different pathologic conditions, and 2) dose, duration, and time of initiation of glutamine-enriched diets.

The sources consulted for the search were MEDLINE, EMBASE, Cochrane Database of Systematic Reviews, Healthstar and HSTAT. Ninety-one studies were assessed; after a methodologic review (primary review), only 16 studies met the inclusion criteria for analysis by a group of experts (secondary review). The coordinators supervised all data, and a final consensus was reached among the coordinators, experts, and methodologists.

Glutamine-enriched diets showed good overall tolerance, improvement of immunologic aspects in multiple trauma patients, cost reduction in critically ill patients, and improvement of mucositis in post-chemotherapy patients (grade B recommendations). The doses given and the duration of therapy varied widely depending on the pathologic condition. Intake of 20 to 30 g/d, early initiation of diet, and maintenance for 5 d or longer are recommended (grade C recommendations).