Study group discussion: Alcoholic liver disease, hepatic encephalopathy and stigmata

What is fetor hepaticus?

The characteristic odor in hepatic encephalopathy.

Mechanism?

Caused by volatile aromatic substances that accumulate in the blood and urine due to defective hepatic metabolism Also called as "liver breath"

When the liver fails to filter out toxins, such as ammonia, there is no place for the toxins to go but into the blood. Significant toxin accumulation causes hepatic encephalopathy, or compromised brain function. With hepatic encephalopathy, as the tainted blood moves through the lungs the toxins are expelled in breath, creating fetor hepaticus.

Ammonia is a byproduct of the digestion of proteins by bacteria in the intestines; normally ammonia is metabolized into urea by the liver and excreted by the kidneys as urine.

What is the portosystemic shunt mechanism?

The shunt allows mercaptans to pass directly to lungs, which is why the characteristic odor is present.

How are mercaptans formed?

Formed by the breakdown of methionine.

Mercaptans are formed by the action of bacteria on sulphur containing proteins.

Review question: Which amino acid contains sulfur?

Methionine is a sulphur containing amino acid.

Review question: Stigmata of alcoholism?

Spider nevi
Dupuytren's contracture
Contracture of palmar fascia
Palmar erythema
Fetor hepaticus
Leukonychia
Testicular atropy
Asterexis
Gynecomastia
Caput medusae

Psoriasis & Eczema... More common in heavy drinkers!