OVERVIEW
Vanishing bile duct syndrome (VBDS) is a pathologic concept of a group of clinical disorders in which intrahepatic cholestasis occurs as a result of inflammation of the intrahepatic bile ducts due to different causes, leading to destruction of the bile ducts, resulting in the loss of localized or diffuse intrahepatic bile ducts. It can be caused by developmental, immunologic, vascular, infectious, or chemical mechanisms. The disease has an insidious onset and presents with jaundice, pruritus, fatigue, and weight loss. Aminotransferases, bilirubin and alkaline phosphatase are also elevated to varying degrees. Treatment is based on the different etiologies and active treatment of the primary disease.
Etiology
There are many causes that can lead to intrahepatic bile duct injury, including: ischemia, infection, abnormal immune response, metabolic abnormality, drugs or poisons. Specific causes are common:
1. Bile duct deficiency syndrome after liver transplantation is the main manifestation of late rejection after liver transplantation.
2.Drugs include: chlorpromazine, cotrimoxazole, clindamycin, ampicillin, amoxicillin, fluoroquinolones, hodgkin’s alkaloids, ibuprofen, itraconazole, and gold preparations.
3. Hodgkin’s disease.
4. cytomegalovirus infection especially after liver transplantation.
Symptoms
The onset is insidious, with progressive liver function deterioration. After liver transplantation, there may be an outbreak of the disease. Mainly manifestations of intrahepatic cholestasis, such as jaundice, itchy skin, fatigue and weight loss. Aminotransferases, bilirubin and alkaline phosphatase are elevated. Advanced patients may show biliary cirrhosis.
Examination
Laboratory tests show abnormal liver function, marked elevation of serum alkaline phosphatase and gamma-glutamyl transpeptidase, and increased bilirubin, with a predominance of increased direct bilirubin. There may be increased non-specific immunoglobulins, and various antibodies such as ANA, AMA and SMA are negative.
Liver biopsy shows a marked reduction or absence of bile ducts. The disease is diagnosed only if “appropriate liver biopsy specimen (liver tissue >3 cm long, containing at least 11 hilar zones)” confirms >50% loss of interlobular bile ducts in the hilar zones.
Diagnosis
The diagnosis is aided by the history, clinical manifestations of intrahepatic cholestasis, and pathologic tissue biopsy. The disease should also be differentiated from other diseases that can cause intrahepatic cholestasis.
Treatment
Treat the primary disease according to the different etiologic factors. For example, strengthen the anti-rejection therapy, avoid the use of suspicious drugs or poisons, and control the infection. If jaundice or skin itching occurs, corticosteroids and ursodeoxycholic acid can be used, which can effectively relieve the symptoms. Liver transplantation is feasible in patients with advanced disease. Liver transplantation may be repeated in those who develop the disease that caused it after liver transplantation.