Olfactory function in dialysis patients: a potential key to understanding the uremic state.

Impaired olfactory function is a marker of neurologic dysfunction in the uremic state. Retained uremic toxins not adequately cleared with dialysis may undermine the integrity of the olfactory epithelium and olfactory bulb and malign central olfactory processing. The evidence suggests that only renal transplantation, with its concomitant thorough reversal of uremia, truly restores olfactory function to normal in end-stage renal disease. Testing of olfactory function may emerge as an important marker for the extent and resolution of uremia.