New insights in uremic toxicity.

The uremic syndrome is characterised by the retention of a host of compounds that in healthy subjects are secreted by the kidneys into normal urine. These compounds disturb many physiologic functions, resulting in toxicity. Many of the responsible compounds remain unknown, however, as well as many patho-physiologic actions of the known retention solutes. In this publication, we review recent new information regarding uremic toxicity. Especially difficult to remove compounds, such as protein bound and larger molecules, seem to play a role. New strategies enhancing their removal might be highly useful.