<prompt> Low serum haptoglobin in hemolysis is masked by ?PregnancyLiver diseaseBile duct obstructionMalnutrition  <response>: Ans. is c i.e., Bile duct obstruction Haptoglobin o Haptoglobin is a transpo glycoprotein which binds free hemoglobin in plasma and carries it to the reticuloendothelial system. It is synthesized in the liver. o A decrease in haptoglobin levels with normal liver function occurs when there is excess of hemoglobin in the plasma due to intravascular hemolysis --- free hemoglobin in plasma bound to haptoglobin and this complex is rapidly cleared by mononuclear phagocytic system. o In biliary obstruction the serum haptoglobin level is increased and this may mask the decrease in serum haptoglobin due to hemolysis. 