Diagnostic Approach to Abnormal Liver Tests Following Liver Transplantation

Routine monitoring of liver tests throughout the early and late period following liver transplant is essential in detecting liver allograft injury. Causes of abnormal liver tests after transplant can be related to allograft integrity (primary graft non-function, delayed graft function), vascular problems (hepatic artery thrombosis, outflow obstruction), biliary problems (bile leak, biliary strictures), infections, immune reactions (acute or chronic rejection, autoimmune hepatitis), and recurrent disease (particularly hepatitis C). Ultrasound of the liver with Doppler examination of the hepatic artery is usually the first step in assessing abnormal tests and may detect biliary abnormalities and/or impaired hepatic artery flow. If the clinical suspicion for a biliary or vascular problem remains high despite a normal ultrasound then magnetic resonance cholangiopancreatography or angiography may be more sensitive. Liver biopsy is essential in making the diagnosis of rejection or recurrent disease. Interpretation of biopsy findings by a skilled pathologist is essential to establishing a correct diagnosis.