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Pseudohyponatraemia in a patient with obstructive jaundice
Mia le Riche1, Lesley J Burgess, A David Marais
1Department of Chemical Pathology, National Health Laboratory Service (NHLS), Tygerberg Hospital, University of Stellenbosch, P.O. Box 19113, Tygerberg 7505, Parow, South Africa. mleriche@sun.ac.za
Clinica Chimica Acta; International Journal of Clinical Chemistry
|November 18, 2005
Summary
Severe hypercholesterolaemia can cause pseudohyponatraemia (falsely low sodium). This occurs due to lipoprotein X (LpX) in obstructive jaundice, requiring consideration in lab results.
Area of Science:
- Clinical Chemistry
- Lipid Metabolism
- Hepatology
Background:
- Pseudohyponatraemia is a rare condition.
- Severe hypercholesterolaemia is often linked to obstructive jaundice.
- Lipoprotein X (LpX) is an abnormal lipoprotein associated with obstructive jaundice.
Observation:
- A case of falsely low sodium measurements is presented.
- The patient had severe hypercholesterolaemia due to obstructive liver disease.
- The role of LpX in pseudohyponatraemia was investigated.
Findings:
- Lipoprotein X (LpX) can cause pseudohyponatraemia.
- Analytical interference from LpX leads to falsely low sodium levels.
- Obstructive jaundice is a key factor in LpX-associated pseudohyponatraemia.
Implications:
- Clinicians should consider pseudohyponatraemia in patients with severe hypercholesterolaemia.
- Accurate diagnosis requires awareness of LpX's analytical effects.
- This finding highlights the importance of correlating lab results with clinical presentation.
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