What is the most common cause of hyperkalemia related to laboratory measurements?

What is the most common cause of hyperkalemia related to laboratory measurements?

• A. Lab error with redraw
• B. Excess dietary potassium
• C. Hyperglycemia
• D. Hypoaldosteronism

Answer: (A)

Potassium is mostly inside cells, so if the blood sample is hemolyzed during collection or handling, potassium leaks out of red blood cells and into the serum. This artifact makes the measured potassium appear falsely high, even though the patient’s true potassium may be normal. Because this lab error with a redraw is the most common reason for seeing elevated potassium purely due to how the specimen was collected, repeating the test after ensuring an clean, non-hemolyzed sample will often reveal a normal value. Dietary potassium, hyperglycemia, and hypoaldosteronism can cause real shifts in potassium, but they aren’t artifacts of the measurement itself.

Potassium is mostly inside cells, so if the blood sample is hemolyzed during collection or handling, potassium leaks out of red blood cells and into the serum. This artifact makes the measured potassium appear falsely high, even though the patient’s true potassium may be normal. Because this lab error with a redraw is the most common reason for seeing elevated potassium purely due to how the specimen was collected, repeating the test after ensuring an clean, non-hemolyzed sample will often reveal a normal value. Dietary potassium, hyperglycemia, and hypoaldosteronism can cause real shifts in potassium, but they aren’t artifacts of the measurement itself.