The effect of haemodialysis on cerebrospinal fluid and plasma amino acids.

The concentration of free amino acids in CSF and plasma has been measured in 19 patients with renal disease undergoing haemodialysis therapy. The values obtained have been compared with those measured in non-haemodialysed patients. At the end of a 10-h dialysis period, the total CSF amino acid concentration had fallen by only 23.3% compared with a 57.7% fall in plasma. Examination of the results for individual amino acid concentrations showed 3 different patterns of inter-relationship between plasma and CSF.