Pseudohypercalcemia in Multiple Myeloma: A Case Report

Area of Science:

• Oncology
• Clinical Biochemistry

Background:

• Hypercalcemia is a frequent complication in multiple myeloma patients.
• Clinical symptoms of hypercalcemia correlate with serum calcium levels.

Observation:

• Pseudohypercalcemia occurs when normal ionized calcium (Ca (I)) is masked by high total serum calcium due to immunoglobulin binding.
• True hypercalcemia involves elevated serum calcium and ionized calcium levels.

Findings:

• Measurement of ionized calcium is critical in asymptomatic multiple myeloma patients with moderate to severe hypercalcemia.
• This case highlights an asymptomatic 44-year-old male with multiple myeloma presenting severe hypercalcemia but a normal serum ionized calcium level, indicating pseudohypercalcemia.

Implications:

• Distinguishing pseudohypercalcemia from true hypercalcemia is essential for appropriate patient management.
• Accurate diagnosis prevents unnecessary treatment for true hypercalcemia in patients with multiple myeloma.