pseudohyperkalemia

A spurious elevation of the serum concentration of potassium occurring when potassium is released in vitro from cells in a blood sample collected for a potassium measurement. This may be a consequence of disease ( i.e., myeloproliferative disorders with marked leukocytosis or thrombocytosis) or as a result of improper collection technique with in vitro hemolysis. [pseudo + G. hyper, above + L. kalium, potassium, G. haima, blood]

* * *

pseu·do·hy·per·ka·le·mia (soo″do-hi″pər-kə-leґme-ə) a laboratory artifact in which serum potassium is elevated when plasma potassium is normal. It occurs in the presence of thrombocytosis or leukocytosis, most commonly in myeloproliferative disorders, because blood clotting causes the release of potassium from platelets and leukocytes.