Loss of amino acids during hemodialysis: quantitative and qualitative investigations.

In three patients the total amino acid losses (free plus peptide-bound) in dialyzate have been assayed by means of gas-liquid chromatography. During a period 3--4 months the average losses varied from 115--178 mg per kg of body weight per dialysis treatment. The weekly mean essential amino acid losses amounted to 3--4% of the dietary intake. The concentrations in the dialyzate of non-essential amino acid fell considerably during the dialysis procedure, whereas the concentrations of most of the essential amino acids remained at a fairly constant level. It is concluded that considerable quantitative but no qualitative differences exist between the patients with respect to amino acid losses.