[lemontea88]

Hey guys,

Just want to ask, in cases of extravascular hemolysis, the pigment stone that forms as a complication of this condition is composed what which type of bilirubin? Conjugated or unconjugated bilirubin?

 

[Dr. N Elham]

Reason for it

Good Question Doctor!
If a pigment stone is formed in billiary tract ( including the gallbladder ) it obviously has passed the hepatocyte, and you know that billirubin can not pass a hepatocyte without being conjugated to glucuronic acid. So the answer is that the pigment will be conjugated.

 

[khanar]

Unconjugated bilirubin can exist in hepatic bile. There are many theories about it but it's not yet fully understood. The only proved cases so far is that in cholangitis the bacteria has glucoronidase activity breaking up the conjugated bilirubin to unconjugated

This article may help
http://www.springerlink.com/content/r831244136297785/

 

[monisia]

in kaplan it says that the pigment stones are composed of unconjugated bilirubin and calcium.

 

[noothan]

So both are possible ??

In that case disease or condition specific ??

Bacterial cholangitis : unconjugated ....................and

 

[Mondoshawan]

I think it is unconjugated bilirubin that will precipitate out with calcium as calcium bilirubinate. If conjugated bilirubin precipitated out, wouldn't we all have pigment stones?

 

[apx85]

I think it is unconjugated bilirubin that will precipitate out with calcium as calcium bilirubinate. If conjugated bilirubin precipitated out, wouldn't we all have pigment stones?

I agree with Mondoshowan. Unconjugated bilirubin is not very water soluble, which is why it needs to be conjugated in the first place. Conjugation of bile is meant to make it water soluble so that it can be excreted.

Normally 98% of bile that is in the biliary tract is conjugated and the remaining 2% is unconjugated. When there is a high concentration of unconjugated bilirubin, this can spill over into the biliary system (overwhelm hepatocytes) and lead to stone formation