Elimination of amino acids in renal failure

The elimination of intravenously infused amino acids was evaluated in six patients with acute renal failure (ARF), 6 with conservatively treated chronic renal failure (CRF), 6 subjects receiving regular hemodialysis treatment (RDT), and 5 healthy control subjects. In ARF, CRF, and RDT groups, whole-body clearance (Cltot) of the 10 amino acids was elevated (113.5 +/- 1.5; 94.2 +/- 1.5 and 127.6 +/- 12.4, respectively, vs 85.2 +/- 4.8 mL.kg-1.min-1 in control subjects, P < 0.001). In ARF, Cltot of histidine, lysine, and methionine was higher and Cltot of phenylalanine and valine was lower as compared with control subjects. In CRF, Cltot of tryptophan and histidine was elevated and Cltot of phenylalanine was reduced; in RDT, Cltot of histidine, methionine, tryptophan, lysine, isoleucine, and leucine was raised. In all groups the relative clearance (% of total clearance) of phenylalanine and valine was reduced, and relative clearance of histidine and tryptophan was elevated. We conclude that in renal failure the elimination of amino acids from the intravascular space is profoundly altered and that the pattern of metabolic aberrations is similar in ARF, CRF, and RDT groups.