biliary cast syndrome
Biliary cast syndrome is a complication that occurs after liver transplantation, where dark solid bilirubin casts develop in the biliary tree, causing biliary obstruction.
Terminology
This should be differentiated from biliary sludge, which represents thickened bile that has not precipitated.
Epidemiology
It occurs in about 4% to 18% of the liver transplantation, mainly in the first 6 months and most often in liver transplantation from donation after cardiac death donors (DCD) .
Clinical presentation
The most common presentation is with fever since the transplanted liver is insensitive/denervated. Laboratory tests will show cholestatic findings.
Pathology
The hard casts are composed of bilirubin (up to 50%) and of bile acids (10-15%) . They are thought to result from cold ischemia during the transplantation, but this has been disputed and other factors include acute rejection on a cellular basis, biliary infection and biliary obstruction .
Radiographic features
Endoscopic retrograde cholangiopancreatography (ERCP)
ERCP is usually the first line of imaging because it offers the ability to perform cholangioplasty if necessary. Areas of stricture, dilation and filling defects may be demonstrated .
CT
Irregular bile duct dilatation. Bile casts can manifest as linear hyperdense material within bile ducts.
MRI
- T1: biliary casts appear hyperintense
Treatment and prognosis
It carries a greater mortality risk and can result in the need for another liver transplantation .
They are usually treated during an ERCP with a sphincterotomy, cast removal, and bile duct stenting.
Alternatives include percutaneous bile duct drainage and irrigation or surgical cast removal.
History and etymology
It was originally described in 1975 by Waldram, Williams, and Calne .