title: Pseudohyperkalemia occurring in a patient with chronic renal failure and polycythemia vera without severe leukocytosis or thrombocytosis.
abstract: Pseudohyperkalemia is defined as a serum potassium concentration 0.4 mEq/l greater than the plasma concentration. The basis of this phenomenon is the release of intracellular potassium from platelets, leukocytes, or erythrocytes, commonly in the setting of extreme leukocytosis (> 10 x 10(4)/microl) or thrombocytosis (> 60 x 10(4)/microl). We report a case of pseudohyperkalemia in a patient with chronic renal failure and polycythemia vera without the finding of severe leukocytosis or thrombocytosis (white blood cell count 1.88 x 10(4)/microl and platelet count 37.9 x 10(4)/microl, respectively). The serum potassium concentration was 8.2 mEq/l, while the plasma potassium level was 6.4 mEq/l in a sample obtained simultaneously. The concentrations of platelet factor IV and beta-thromboglobulin, known to be markers of platelet activation, were greater than 100 ng/ml and 200 ng/ml, respectively, indicating that platelet activation may have been related to the development of pseudohyperkalemia in this patient. These findings suggest that pseudohyperkalemia should be considered when hyperkalemia is seen in a patient with chronic renal failure and myeloproliferative disorders.
authors.affiliation: First Department of Medicine, Hamamatsu University School of Medicine, Hamamatsu, Japan. fukasawa@hama-med.ac.jp
authors.forename: H
authors.initials: H
authors.lastname: Fukasawa
authors.forename: R
authors.initials: R
authors.lastname: Furuya
authors.forename: A
authors.initials: A
authors.lastname: Kato
authors.forename: K
authors.initials: K
authors.lastname: Yonemura
authors.forename: Y
authors.initials: Y
authors.lastname: Fujigaki
authors.forename: T
authors.initials: T
authors.lastname: Yamamoto
authors.forename: A
authors.initials: A
authors.lastname: Hishida
mesh_terms: D000368:Aged; D006801:Humans; D006947:Hyperkalemia / Q000150:complications* / Q000175:diagnosis; D007676:Kidney Failure, Chronic / Q000150:complications*; D007964:Leukocytosis; D008297:Male; D011087:Polycythemia Vera / Q000150:complications*; D011188:Potassium / Q000097:blood; D013922:Thrombocytosis
chemical_list: D011188:Potassium