Dubin-Johnson syndrome.

A young man presented with recurrent episodes of mild jaundice. Apart from conjugated hyperbilirubinemia, other liver function tests were always normal. Clinical suspicion of Dubin-Johnson syndrome was raised. Liver biopsy showed diffuse deposition of coarse granular dark brown pigment in hepatocytes. Dubin-Johnson syndrome is a benign condition, which results from a hereditary defect in biliary secretion of bilirubin pigments, and manifests as recurrent jaundice with conjugated hyperbilirubinemia. The defect is due to the absence of the canalicular protein MRP2 located on chromosomes 10q 24, which is responsible for the transport of biliary glucuronides and related organic anions into bile. No treatment is necessary and patients have a normal life expectancy.