What is the value of plasma/serum aluminum in patients with chronic renal failure?

In a region with a relatively low incidence of aluminum toxicity water, dialysis fluid and plasma aluminum were monitored in hemodialysis patients before and after the introduction of reverse osmosis (RO) water. Before the use of RO water, there was a close correlation between plasma and dialysis fluid aluminum with exposure to aluminum being reflected equally by either water, dialysis fluid or plasma aluminum. Patients with clinical manifestations of aluminum toxicity were characterised by a plasma aluminum consistently greater than mumol/l and a dialysis fluid aluminum consistently greater than 1 mumol/l. No evidence of clinical toxicity was found in patients in whom the plasma aluminum was maintained up to 5 mumol/l. Following the introduction of RO water, the dialysis fluid aluminum was able to be maintained less than 1 mumol/l, the plasma aluminum fell and no new cases of clinical toxicity were identified over the following five years. An effect of aluminum hydroxide dosage on plasma aluminum could be identified only in patients in whom the dialysis fluid aluminum was less than 1 mumol/l. Plasma aluminum was found to be a poor guide to bone stores but appeared to correlate better with the presence of bone toxicity than total bone aluminum. Regular monitoring of dialysis fluid and plasma aluminum is recommended as a means of detecting exposure to aluminum as well as the source of exposure and as a guide to the risk of clinical toxicity.