Pseudohyperkalemia Associated With Leukemia

Abstract

Elevated potassium levels can be a life-threatening emergency. We describe a case of falsely elevated serum potassium level in a patient with leukemia, which was suspected to be falsely elevated because the patient was asymptomatic with a normal electrocardiogram (EKG). Common reasons behind such a discrepancy in leukemia patients are the use of a tourniquet before collection, use of vacuum/pneumatic tubes for transportation, prolonged periods of incubation, use of heparin for sample collection, and processing of samples via centrifugation. Since the process is related to the method of collection and processing, we recommend using rapid point of care testing in such cases to differentiate between false and true potassium elevation, as it is a well-validated tool. Moreover, there is a good correlation between potassium measured with the blood gas, point of care, and central laboratory analyzers when the concentration of potassium is above 3 mEq/L.

CASE-3: Dr. Hani Ajrina Zulkeflee, Dr Wan Nur Aimi Wan Mohd Zamri, Dr Siti Nadirah Ab Rahim, Dr Wan Nor Fazila Hafizan Wan Nik and Dr Razan Hayati Zulkeflee

“…The most suitable method for monitoring the patient's potassium levels is through whole blood potassium analysis using a direct ion-selective electrode method through the blood gas analyser. 3,8 This approach aids in distinguishing between true and erroneous hyperkalaemia Additionally, it is imperative for clinicians to correlate blood test results with clinical findings. Effective communication between clinicians and laboratory personnel becomes essential when reported results show discrepancies.…”

“…Alternatively, utilizing a direct ion-selective electrode method through a blood gas analyser for the measurement of whole blood potassium offers a swift method to identify true hyperkalaemia, as it bypasses the technical processing of a patient's sample. 3 Red blood cell haemolysis is the predominant preanalytical factor leading to pseudohyperkalaemia. Any reported potassium concentration surpassing the reference range necessitates an accompanying assessment of the haemolysis index (H-index).…”