An outbreak of dialysis dementia due to aluminum in the dialysate.

The dialysis dementia syndrome was observed in eight of 21 patients dialyzed in a small center during a 22-month period in which dialysate contained aluminum levels of 618 microgram/liter. This incidence of 38% was significantly higher than the zero incidence of four prior years when no aluminum was added to city water (p less than 0.05) and also when compared to the zero incidence in the 2.5 years subsequent to deionization of dialysis water which lowered its aluminum content to less than 1 microgram/liter (p less than 0.0002). Since other factors were not altered, we conclude that aluminum intoxication from the dialysate was the cause for the outbreak of this progressive encephalopathy.