Pseudohyponatraemia in a patient with obstructive jaundice

IntroductionPseudohyponatraemia is uncommonly associated with severe hypercholesterolaemia. Severe hypercholesterolaemia encountered in obstructive jaundice due to an abnormal lipoprotein, lipoprotein X (LpX), may result in pseudohyponatraemia.Case reportWe report a case of falsely low sodium measurements in a patient with severe hypercholesterolaemia due to obstructive liver disease. The pathophysiology, complications and analytical effects of LpX are briefly discussed.ConclusionThe possibility of pseudohyponatraemia should be considered in severely hypercholesterolaemic samples.