Pseudohyperkalemia without reported haemolysis in a patient with chronic lymphocytic leukaemia

BMJ Case Rep. 2012 Jan 10:2012:bcr1220115330. doi: 10.1136/bcr.12.2011.5330.


Hyperkalemia is a medical condition that requires immediate recognition and treatment to prevent the development of life-threatening arrhythmias. Pseudohyperkalemia is most commonly due to specimen haemolysis and is often recognised by laboratory scientists who subsequently report test results with cautionary warnings. The authors present a case of pseudohyperkalemia in a patient with chronic lymphocytic leukaemia that was the result of white blood cell lysis during phlebotomy. False elevations of potassium from this condition may not be reported with a warning from the laboratory. This places the patient at risk of unnecessary and potentially dangerous treatments. This phenomenon has not been published in the emergency medicine literature to date.

Publication types

  • Case Reports

MeSH terms

  • Aged
  • Diagnosis, Differential
  • Humans
  • Hyperkalemia / blood
  • Hyperkalemia / diagnosis
  • Hyperkalemia / etiology*
  • Leukemia, Lymphocytic, Chronic, B-Cell / blood
  • Leukemia, Lymphocytic, Chronic, B-Cell / complications*
  • Leukemia, Lymphocytic, Chronic, B-Cell / diagnosis
  • Leukocytes / pathology*
  • Male
  • Phlebotomy / adverse effects*
  • Potassium / blood*
  • Tumor Lysis Syndrome / diagnosis*


  • Potassium