Hypoparathyroidism: pathophysiology and diagnosis

Calcium plays a vital role in nearly all cells in the body. As a result, calcium homeostasis is precisely regulated through the actions of parathyroid hormone (PTH), vitamin D, and calcitonin. Hypoparathyroidism is an endocrine disorder characterized by a deficiency in PTH, resulting in hypocalcemia and hyperphosphatemia. Causes include immune-mediated, surgical gland destruction and hypomagnesemia, among other conditions better defined in humans. Hypocalcemia results primarily in neurologic and neuromuscular abnormalities, including generalized seizures. A diagnosis can be made based on the presence of hypocalcemia, hyperphosphatemia, and inappropriately low PTH levels as well as exclusion of other causes of hypocalcemia, especially renal disease.