cholestasis
Meaning of cholestasis: Yellow skin, itching, dark urine and pale stools all trace back to bile that cannot leave the liver by its usual route.
Definition of cholestasis
Cholestasis is any condition in which bile stops flowing normally out of the liver. Bile is the greenish fluid the liver makes to help digest fat and to carry off waste, including bilirubin, the pigment left over when worn out red blood cells are broken down. When the flow slows or stops, those components back up into the blood.
How cholestasis is built
- chol/e, chol/o Combining form · Greek bile, gall
- -stasis Suffix · Greek stopping, controlling, standing still
A medical term is read from its ending backwards: the suffix first, then the prefix, then the root. See all 223 word parts.
Where can the blockage sit?
| Intrahepatic | Extrahepatic | |
|---|---|---|
| Location | Inside the liver, in the cells or the smallest ducts | In the larger ducts outside the liver |
| Typical causes | Hepatitis, alcohol related liver disease, certain medications, cholestasis of pregnancy, primary biliary cholangitis | Gallstones, a stricture, a tumor of the pancreas head or the duct itself |
| What imaging shows | Ducts of normal caliber | Ducts widened above the obstruction |
The two produce a similar pattern on blood testing, so imaging is what separates them. Ultrasound of the bile duct system is usually the first look, since a dilated duct points outward, toward a mechanical obstruction somewhere along the path to the common bile duct and the intestine, while normal caliber ducts point back into the liver itself.
Why does the skin turn yellow and itch?
Bile that cannot leave by the intestine leaves instead by the bloodstream. Bilirubin builds up and stains the skin and the whites of the eyes yellow, a change called jaundice. The kidneys clear some of the excess, which darkens the urine to the color of tea or cola. Meanwhile the pigment never reaches the gut, so stools lose their brown color and turn pale or clay colored. Itching, which can be intense and is often worse at night, is thought to come from substances retained along with the bile rather than from bilirubin itself, which explains why it does not track neatly with how yellow a person looks.
What else does blocked bile affect?
Bile also does a job in digestion. Without it reaching the intestine, fat is absorbed poorly, stools become greasy and hard to flush, and the vitamins that dissolve in fat, namely A, D, E and K, are taken up less well. A shortfall of vitamin K matters because the liver needs it to build several clotting factors, so prolonged cholestasis can lengthen bleeding times. Blood tests reflect the pattern, with a marked rise in alkaline phosphatase and gamma glutamyl transferase alongside the bilirubin.
Used in a sentence
Laboratory testing showed findings consistent with cholestasis, prompting further imaging of the bile ducts.
Good to know
Intrahepatic and extrahepatic cholestasis produce similar laboratory findings but arise at different points along the bile pathway, which is why imaging of the ducts rather than blood testing alone separates the two.
Word origin
Where “cholestasis” comes from
Formed from chole-, from Greek khole, meaning bile, and stasis, from Greek stasis, meaning a standing still or stoppage.