Pterin Metabolism In Haemodialysis Patients

Abstract

Patients undertaking maintenance haemodialysis may develop a variety of neurological disorders, the most serious of which is aluminium induced encephalopathy. Abnormally raised serum concentrations of pterins are found in dialysis patients, and neonates with tetrahydrobiopterin deficiency develop mental dysfunction. Dihydropteridine reductase, essential for maintenance of normal levels of tetrahydrobiopterin, is inhibited when aluminium is added to brain homogenate at similar concentrations to those found in aluminium encephalopathy. We have previously shown that erythrocyte dihydropteridine reductase activity was reduced in non-encephalopathic dialysis patients and inversely related to serum aluminium concentration. Concentrations of serum biopterin derivatives were raised but not related to either aluminium or dihydropteridine reductase.