Biochemical Profile of Uremic Breath

Publisher Website
Google Scholar
Abstract
We attempted to define the substances that contribute to the characteristic "uremic breath" of patients with end-stage renal disease. Breath samples from nine patients underwent direct analysis before and after hemodialysis with use of gas chromatography and confirmation by mass spectrometry, and indirectly assessment by an organoleptic panel. Concentrations of secondary and tertiary amines, dimethylamine and trimethylamine were increased, with subsequent reduction after hemodialysis (dimethylamine from 2.00±0.19 [S.E.M.] to 0.88±0.12 μg per 30 minutes, P<0.001, and trimethylamine from 0.79±0.22 to 0.44±0.15 μg per 30 minutes, P<0.003). Treatment with nonabsorbable antibiotics in two patients reduced both serum and breath amine levels without dialysis. Loss of nitrogen via the breath was not quantitatively important. We conclude that uremic breath reflects the systemic accumulation of potentially toxic volatile metabolites, among which dimethylamine and trimethylamine have been positively identified and correlated with the classic fishy odor. (N Engl J Med 297:132–135, 1977)