Serum Levels of Acetate and TCA Cycle Intermediates during Hemodialysis in Relation to Symptoms

Abstract

In order to study the metabolism of acetate transfered from dialysate, the plasma concentrations of organic acids including the tricarboxylic acid cycle (TCA cycle) intermediates were measured during hemodialysis in a comparative study between acetate dialysate and bicarbonate dialysate in 17 patients on maintenance hemodialysis treatment. Continuous measurements of serum concentrations of these organic acids during hemodialysis were performed using the filtrate obtained through an ultrafiltrate sampling device. The organic acids were measured by isotachophoresis. Serum acetate, malate and citrate concentration increased with time in acetate dialysis compared with bicarbonate dialysis. Correlations were found between these organic acids. Isocitrate became detectable when the serum acetate concentration was over 7 mmol/l which was correlated to the acetate concentration, and was accompanied by the development of symptoms. The above results suggest that an acetate overload on the patients during acetate dialysis affects acetate metabolism through the TCA cycle resulting in an accumulation of organic acids in the serum and the development of symptoms.