Amino acid solutions for CAPD: rationale and clinical experience

Protein-calorie malnutrition is present in a sizable proportion of dialysis patients. In CAPD patients, constant glucose absorption from dialysate may displace other calorie sources, such as protein, and may suppress the appetite, thus contributing to malnutrition. Use of amino acids in place of glucose as the osmotic agent has been studied extensively. Ultrafiltration and small-molecule clearance similar to that with glucose can be achieved with amino acid solutions, but nitrogenous waste produced by amino acids limits the extent to which they can replace hypertonic glucose. Side effects of CAPD with amino acids appear to be minor and easily manageable. Most studies have found at least some nutritional benefit of amino acid solutions in addition to that of lowering the glucose load. Short-term studies of amino acid solutions for dialysis indicate that they may improve protein nutrition in malnourished CAPD patients.