This is not specifically a disease itself.  It is rather a symptom or result of other diseases.

Cholestasis is an impairment of bile flow from the liver to the intestines

It can also be as a result of decreased production.  Bile is formed in the liver

Stoppage can be catagorized as obstructive or metabolic

Obstructive can be as a result of a gallstone or a malignancy

Metabolic occurs due to an adverse effect of a medicaiton or a genetic causation.

Increased conjugated bilirubin

Mild increase in liver enzymes can be seen

Symptoms

   -  Hypercholemia [increased serum bile salt concentration]
   -  Pruritus  [Itching]
   -  Jaundice
   -  Dark urine
   -  Hyperlipidemia
   -  Xanthomas
   -  Failure to thrive

Ultrasound and CT may be benifical
Biliary nuclear medicine study [HIDA]
Liver biopsy

Treatments

   -  Ursodeoxycholic acid
   -  Cholestyramine
   -  Phenobarbital
   -  Phytonadione (Vitamin K)
   -  Alpha tocopherol (Vitamin E)
   -  Vitamin A
   -  Ergocalciferol  (Vitamin D)
   -  Antibiotics
   -  Surgery
   -  ERC
   -  Percutaneous transhepatic Cholangiography
   -  Removal of Gallbladder if appropriate