Ca and albumin

Q: Severe volume depletion tends to cause? (select one)

A) pseudohypercalcemia

B) pseudohypocalcemia 

Answer: A

This question aims to revisit the calcium-albumin relationship. It is well known that calcium level should be adjusted with albumin level as in hypoalbuminemia; total serum calcium concentration may be normal, though actual serum ionized calcium may be elevated.

In contrast, few clinicians pay attention to situations that may cause hyperalbuminemia, such as severe volume depletion and multiple myeloma. In such situations, the reverse happens with elevated serum total calcium concentration, where actual serum ionized calcium concentration stays normal. This is called pseudohypercalcemia. It has also been called factitious hypercalcemia, which is a misnomer.

#endocrinology

References:

1. Goltzman D. Approach to Hypercalcemia. [Updated 2023 Apr 17]. In: Feingold KR, Anawalt B, Blackman MR, et al., editors. Endotext [Internet]. South Dartmouth (MA): MDText.com, Inc.; 2000-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK279129/

2. Ashrafi F, Iraj B, Nematollahi P, Darakhshandeh A. Pseudohypercalcemia in Multiple Myeloma: A Case Report. Int J Hematol Oncol Stem Cell Res. 2017 Jul 1;11(3):246-249. PMID: 28989592; PMCID: PMC5625476.

3. Walker MD, Shane E. Hypercalcemia: A Review. JAMA. 2022 Oct 25;328(16):1624-1636. doi: 10.1001/jama.2022.18331. PMID: 36282253.