CAUSES OF HYPERCALCEMIA
Harrison 17th, AIIMS Nov 2007 Q
| Excessive PTH production |
| Primary hyperparathyroidism (adenoma, hyperplasia, rarely carcinoma) |
| Tertiary hyperparathyroidism (long-term stimulation of PTH secretion in renal insufficiency) |
| Ectopic PTH secretion (very rare) |
| Inactivating mutations in the CaSR (FHH) |
| Alterations in CaSR function (lithium therapy) |
| Hypercalcemia of malignancy |
| Overproduction of PTHrP (many solid tumors) |
| Lytic skeletal metastases (breast, myeloma) |
| Excessive 1,25(OH)2D production |
| Granulomatous diseases (sarcoidosis, tuberculosis, silicosis) |
| Lymphomas |
| Vitamin D intoxication |
| Primary increase in bone resorption |
| Hyperthyroidism |
| Immobilization |
| Excessive calcium intake |
| Milk-alkali syndrome |
| Total parenteral nutrition |
| Other causes |
| Endocrine disorders (adrenal insufficiency, pheochromocytoma, VIPoma) |
| Medications (thiazides, vitamin A, antiestrogens) |
Note: CaSR, calcium sensor receptor; FHH, familial hypocalciuric hypercalcemia; PTH, parathyroid hormone; PTHrP, PTH-related peptide.
Additions:-
**William's Syndrome causes hypercalcemia d/t increased sensitivity to Vitamin D, it is also called as Idiopathic Hypercalcemia of Infancy.
**Increased Bone turnover has also been mentioned for Vitamin A Intoxication and for Thiazides.
pgmeenotesby dv.
