Dialysate aluminium concentration and renal bone disease.

We studied 40 patients maintained on regular hemodialysis, using radiology and quantitative bone histology to assess the relationship between renal bone disease and exposure to aluminium. Fractures were significantly more common in patients exposed to high dialysate aluminium concentrations. The histologic indices of osteomalacia were significantly related to the prevailing dialysate aluminium concentration, in such a way that higher aluminium levels were associated with more osteomalacia. Patients who had been exposed to higher concentrations of aluminium also tended to have a lower plasma phosphate concentration, and associated hypercalemia was seen in 6 patients with osteomalacia. These findings suggest that aluminium is a toxic agent associated with a mineralizing defect in the bone of renal failure patients. This may explain the incomplete response of some patients with renal osteomalacia to administration of 1,25-dihydroxy vitamin D.