Hypercalcemia This guideline has been adapted from the Endocrine Testing Guidelines prepared by the Alberta Common Procedure List Committee of Alberta Health, 1994. To use effective laboratory testing to facilitate the investigation of hypercalcemia. To promote the optimal diagnostic laboratory testing strategy to enhance the quality of care for patients in Alberta and to improve laboratory ordering practices. L. The specimen for calcium analysis should be obtained without application of a tourniquet.
Thiazide diuretics can mildly elevate calcium levels.
In mild hypercalcemia, consider discontinuing thiazides for 1 month, then repeat serum calcium. For patients with known malignancy, e.g., myeloma or carcinoma of bronchus, treatment of hypercalcemia may commence at mild to moderate elevations of calcium, without detailed investigation. Refer to algorithm for diagnostic options. The estimated incidence of hypercalcemia due to primary hyperparathyroidism and due to malignancy are 250 cases per million and 150 cases per million respectively. Overall, the incidence of hypercalcemia is about 0.6 percent.