Does glutamine-enriched parenteral nutrition really affect intestinal morphology and gut permeability?

Background: Nutritional depletion has been related to low glutamine levels in plasma and gut mucosa. This study was set up to investigate the effects of glutamine-enriched total parenteral nutrition on intestinal morphology and permeability. Methods: Twenty-three depleted patients were randomized and after stabilization baseline measurements were performed. Plasma glutamine concentrations, gut morphology (including proliferation and lymphocyte markers) and intestinal permeability were measured. After administration during 8–10 days of a glutamine enriched total parenteral nutrition or an isonitrogenous control solution the measurements were repeated. Results: No significant changes in glutamine concentrations, intestinal permeability, mucosal morphology or gut mucosal inflammation were observed between groups. Conclusions: Glutamine enriched total parenteral nutrition in a depleted patient population does not result in improvements in gut morphology and gut barrier function.