From the Guidelines
The evaluation of jaundice should begin with a thorough history and physical examination, followed by laboratory testing to determine the cause, and abdominal ultrasound is recommended as the initial diagnostic test of choice in patients with suspected obstruction of the common duct. The initial tests should include liver function tests (total and direct bilirubin, ALT, AST, alkaline phosphatase, GGT), complete blood count, and coagulation studies to categorize jaundice as pre-hepatic, hepatic, or post-hepatic 1. For suspected pre-hepatic jaundice, hemolysis workup including reticulocyte count, haptoglobin, and peripheral smear is appropriate, while hepatic causes require viral hepatitis serologies, autoimmune markers, and toxicology screening 1.
Key Diagnostic Steps
- Initial laboratory tests to determine the cause of jaundice
- Abdominal ultrasound to assess for biliary dilation
- Advanced imaging like MRCP, ERCP, or CT if obstruction is confirmed
- Liver biopsy in cases of unclear etiology after initial testing
The pattern of laboratory abnormalities guides the diagnostic approach, with elevated unconjugated bilirubin suggesting hemolysis or genetic disorders like Gilbert's syndrome, while elevated conjugated bilirubin with increased alkaline phosphatase points to biliary obstruction 1. Elevated transaminases typically indicate hepatocellular injury. This systematic approach allows for efficient diagnosis and appropriate management of the underlying cause of jaundice. Abdominal ultrasound is particularly useful in detecting cirrhosis and biliary obstruction, with a sensitivity of 65% to 95% for cirrhosis and a positive predictive value of 98% 1.
From the Research
Approach to Evaluating Jaundice
The evaluation of jaundice involves a comprehensive approach to determine the underlying cause of hyperbilirubinemia. The following steps are recommended:
- A thorough medical history, review of systems, and physical examination to identify potential causes of jaundice, such as alcoholic liver disease, biliary strictures, choledocholithiasis, drug-induced liver injury, hemolysis, or hepatitis 2, 3
- Initial laboratory evaluation, including:
- Bilirubin (total and fractionated) to determine the type of hyperbilirubinemia (conjugated or unconjugated) 2, 3, 4
- Complete blood cell count 2, 3
- Liver function tests, such as aspartate transaminase, alanine transaminase, gamma-glutamyltransferase, and alkaline phosphatase 2, 3, 4
- Prothrombin time and international normalized ratio to assess hepatic synthetic function 2, 3
- Imaging studies, such as:
- Ultrasonography of the abdomen to evaluate the liver, gallbladder, and biliary tract 2, 5, 3, 4
- Computed tomography with intravenous contrast media to evaluate the liver, bile ducts, and surrounding tissues 2, 5, 4
- Magnetic resonance cholangiopancreatography to evaluate the biliary tract and pancreatic duct 2
- If the etiology of jaundice is unclear, liver biopsy may be necessary to establish the diagnosis, prognosis, and management of the disease 2
Laboratory Evaluation
The laboratory evaluation of jaundice aims to determine the type and severity of hyperbilirubinemia, as well as the underlying cause. The following laboratory tests are recommended:
- Fractionated bilirubin to differentiate between conjugated and unconjugated hyperbilirubinemia 2, 3, 4
- Liver function tests to assess hepatic damage or dysfunction 2, 3, 4
- Complete blood cell count to evaluate for hemolysis or other hematologic disorders 2, 3
Imaging Evaluation
Imaging studies play a crucial role in the evaluation of jaundice, particularly in determining the presence of biliary obstruction or hepatocellular disease. The following imaging modalities are recommended:
- Ultrasonography as the initial imaging study to evaluate the liver, gallbladder, and biliary tract 2, 5, 3, 4
- Computed tomography with intravenous contrast media to evaluate the liver, bile ducts, and surrounding tissues 2, 5, 4
- Magnetic resonance cholangiopancreatography to evaluate the biliary tract and pancreatic duct 2