A patient presents with unconjugated hyperbilirubinemia and presence of urobilinogen in urine. Which amongst the following is the least likely diagnosis?

Dubin Johnson syndrome is a beingn rare disorder characterized by conjugated hyperbilirubinemia. The degree of hyperbilirubinemia increase during illness, pregnancy and with the use of oral contraceptive pills. Physical examination shows jaundice sometimes hepatospleenomegaly. Investigations: shows elevated serum bilirubin levels. Other routine tests are normal. Cardinal feature of DJS is accumulation of dark coarsely granular pigment within the lysosomes of centrilobular hepatocytes. This gives a gross black appearance to the liver. This pigment is derived from epinephrine metabolites that are not excreted. Ref: Harrison's principles of internal medicine 18th edition, Chapter 303.