Sunday 18 March 2007
Cholestasis (cholestatic jaundice)
- extra-hepatic cholestasis
- hepatic tumors
- inflammatory myofibroblastic tumors
- biliary atresia
- choledochal cyst
- extra- and intra-hepatic cholestasis
primary sclerosing cholangitis
- acute liver failure
Causes of jaundice can be divided into prehepatic, hepatic and post hepatic categories. Prehepatic jaundice typically results from hemolysis and is evident on clinical and laboratory studies.
For example, heomolytic disease of the newborn (erythroblastosis fetalis) can lead to significant hyperbilirubinemia which can, in turn, cause significant brain damage. Intrahepatic causes of jaundice include viral hepatitis, cholestatic drug reaction, alcohol toxicity, cirrhosis, and the inherited Gilbert’s syndrome.
Extrahepatic causes of cholestasis include gallstones, obstructing tumors, benign strictures such as one sees secondary to pancreatitis and status post cholecystectomy when the bile duct is injured, and congenital abnormalities such as choledochal cysts, Caroli’s disease and primary sclerosing cholangitis. In general, the serum bilirubin must be greater than 3 mg per deciliter in order for one to appreciate clinical jaundice in a Caucasian patient’s sclera.
The key radiographic feature, which helps in the distinction between extrahepatic and intrahepatic cholestasis, is the presence of dilated bile and pancreatic ducts.
The absence of dilated pancreatic and biliary ducts suggests intrahepatic cholestasis, and necessitates a medical work-up including hepatitis serologies, and perhaps percutaneous liver biopsy.
The presence of dilated ducts generally indicates surgical disease.