endocrine and metabolic disorders
Overview of Disorders of Potassium Concentration
Pseudohypokalemia and pseudohyperkalemia
 or falsely low serum potassium, occasionally is found when blood specimens from patients with Chronic Myeloid Leukemia (CML) and a white blood cell count Pseudohyperkalemia,or falsely elevated serum potassium, is more common, typically occurring due to hemolysis and release of intracellular potassium. To prevent false results, phlebotomy personnel should not rapidly aspirate blood through a narrow-gauge needle or excessively agitate blood samples. Pseudohyperkalemia can also result from platelet count>400,000/mcL (> 400 × 109/L) due to release of potassium from platelets during clotting; in these cases, the plasma potassium (unclotted blood), as opposed to serum potassium, is normal. 