Fetor hepaticus or foetor hepaticus (see spelling differences), also known as breath of the dead, is a condition seen in portal hypertension where portosystemic shunting allows mercaptans to pass directly into the lungs. It is a late sign in liver failure. Other possible causes are the presence of ammonia and ketones in the breath. The breath has a sweet, faecal smell to it.
The compound dimethyl sulfide has been associated with it,[1] raising the possibility of an objective noninvasive measure of liver failure.