a1 Department of Surgery, Maastricht University, PO Box 616, NL-6200 MD Maastricht, The Netherlands
a2 Department of Plastic Surgery, Maastricht University, Maastricht, The Netherlands
a3 Department of Hepatology, Royal Free and University College Medical School, London, UK
The amino acid arginine and one of its metabolites NO have gathered broad attention in the last decade. Although arginine is regarded as a conditionally essential amino acid in disease, L-arginine supplementation in severe illness has not found its way into clinical practice. This might be due to the invalid interpretation of results from studies with immune-enhancing diets containing L-arginine amongst other pharmaconutrients. However, not much attention is given to research using L-arginine as a monotherapy and the possibility of the alternative hypothesis: that L-arginine supplementation is beneficial in disease. The present review will discuss data from studies in healthy and diseased animals and patients with monotherapy of L-arginine to come to an objective overview of positive and negative aspects of L-arginine supplementation in disease with special emphasis on sepsis, cancer, liver failure and wound healing.