Effect of Measuring γ-Glutamyl Transpeptidase and Using Smoflipid in a Parenteral Nutrition Infusion in a Patient With Severe Malabsorption and Overlapping Primary Sclerosing Cholangitis and Ulcerative Colitis
Studies discussing inflammation and oxidative stress state that these conditions are known contributors in the pathogenesis of cholestatic diseases and ulcerative colitis, and studies examining patients with liver disease have found decreased antioxidant status and significant elevation of lipid peroxides as compared with healthy subjects. One hypothesis in liver disease is that deficient antioxidant defense mechanisms may lead to excess oxygen free radical formation, which promotes deleterious processes in the liver. The role of oxidant agents in cells is complex and depends on the balance between oxidant and antioxidant particles, but there is 1 potential marker of oxidative stress that can be readily utilized for our patients who are receiving nutrition support: γ-glutamyl transpeptidase (GGT). GGT is thought to induce oxidative stress in the artery wall in the presence of free iron and is likely an indicator of a depleted supply of glutathione, especially in the liver, which can lead to a cascade of problems related to increased oxidative stress. One could consider giving these patients liposomal glutathione or the components that make up glutathione, such as glycine, glutamine, and N-acetyl-cysteine, but unfortunately total parenteral nutrition (TPN) in the United States contains no cysteine or glutamine. Another possible way would be to give additional antioxidants, such as selenium and zinc, as well as vitamins A, C, and E. In this case report, I demonstrate the potential effect that switching from a straight ω-6 fatty acid solution to a blended fatty acid solution had on liver function tests, specifically GGT, for a 66-year-old patient dependent on TPN for the prior 16 months.