Investigation of jaundice

Jaundice is an important clinical sign reflecting the accumulation of bilirubin in blood. It is frequently associated with significant underlying disease. It can result from increased bilirubin production (due to haemolysis); inability of the liver to take up and/or conjugate bilirubin (in Gilbert’s syndrome or parenchymal liver disease); or failure to excrete bilirubin into biliary canaliculi and/or into the biliary tree (when the bile ducts are obstructed). Appropriate investigation of a jaundiced patient starts with a detailed history that will often give vital clues to the diagnosis. Clinical examination should look for the presence of stigmata of chronic liver disease to determine the possible chronicity of liver injury. Liver function tests (LFTs) include a variety of different biochemical measurements reflecting hepatocyte and cholangiocyte injury, as well as liver synthetic function. Accurate interpretation of the different patterns (hepatitic versus cholestatic) of LFT derangement allows for the efficient choice of further investigations. This review will detail the steps involved in bilirubin metabolism, the causes of jaundice and subsequently the appropriate investigation of a patient with jaundice.