Unexplained hyperkalemia: The tip of the iceberg

Area of Science:

• Internal Medicine
• Hematology
• Clinical Pathology

Background:

• Hyperkalemia is a critical condition, while pseudohyperkalemia is benign.
• Pseudohyperkalemia is suspected with elevated serum potassium without renal dysfunction or other electrolyte imbalances.
• Misdiagnosis of pseudohyperkalemia leads to physician anxiety, excessive testing, and unwarranted treatments.

Purpose of the Study:

• To highlight pseudohyperkalemia as a potential indicator of underlying pathology.
• To emphasize the importance of recognizing pseudohyperkalemia to avoid unnecessary medical interventions.

Main Methods:

• Case report of a 60-year-old woman with persistent hyperkalemia.
• Evaluation of a mean platelet count exceeding 1015×10(3) cells/cumm over six months.
• Hematological assessment revealing essential thrombocythemia, a myeloproliferative disorder.

Main Results:

• Thrombocytosis was identified as the cause of persistent hyperkalemia.
• Essential thrombocythemia was diagnosed based on elevated platelet counts.
• Resolution of hyperkalemia occurred concurrently with the normalization of platelet count.

Conclusions:

• Pseudohyperkalemia can be a sign of a significant underlying pathological process.
• A high index of suspicion is crucial for diagnosing pseudohyperkalemia.
• Underdiagnosis of pseudohyperkalemia leads to unnecessary patient testing and treatment.