Parenteral approaches in malabsorption: Home parenteral nutrition.

Severe malabsorption of fluids and nutrients leads to intestinal failure (IF) where intravenous supplementation of nutrients and fluids is necessary to maintain health and/or growth. Long-term treatment of IF implies the start of intravenous support in the outpatient setting (home parenteral nutrition, HPN). Although HPN has proven lifesaving for many patients for more than four decades this strategy remains associated with complications that compromise the quality of life. Many problems relate to the presence of the venous access device and concern infections or vascular occlusion due to thrombosis. Patient training remains key to prevent these complications. Also metabolic problems may arise that involve liver function or composition or bone mineralization. While intestinal transplantation remains inferior to HPN as alternative treatment strategy in terms of survival, promising developments include the introduction of hormones that promote intestinal adaptation, mixed lipid emulsions that decrease liver problems and catheter lock solutions that prevent infections.

Hyperammonemia in a patient with short bowel syndrome and chronic renal failure.

A patient with short bowel syndrome (SBS) and renal failure developed a disturbance of consciousness with hyperammonemia. Abnormally low concentrations of ornithine, citrulline, and arginine were observed on the plasma aminogram. These results suggested that the activities of amino acid synthetase localized in the small intestinal flora were lost. The small intestine is required for arginine synthesis; thus, infusion limited to the essential amino acids to SBS patients will cause a deficiency of the urea cycle intermediates, ornithine, citrulline, and arginine and may lead to hyperammonemia. In addition, the renal insufficiency may have caused decreased excretion of ammonia. In this patient, supplemental arginine improved the symptoms.