No abstract

Hyperparathyroidism occurs due to increased production of the parathyroid hormone (PTH) from the parathyroid glands. This can stem from abnormal secretion of the hormone as seen in primary and tertiary hyperparathyroidism. It can also be caused by defective homeostasis of the calcium metabolism, which can stimulate the production of PTH as in secondary hyperparathyroidism. The third most common endocrine disorder is primary hyperparathyroidism (PHPT), with its incidence being the highest among postmenopausal women. Seventy to eighty percent are asymptomatic, and the symptoms are related to chronic hypercalcemia rather than the elevated hormone levels. In the symptomatic group, nephrolithiasis is the most common followed by osteoporosis and increased fracture risk. With the advent of new diagnostic modalities, the severe presentation of the disease has decreased. Surgical excision of the gland(s) is a modality of choice for PHPT. Medical management is done using bisphosphonates, hormone replacement therapy, and calcimimetics and is usually required for mild disease. Secondary hyperparathyroidism occurs when the body tries to compensate for the low levels of ionized calcium by overproduction of the hormone. In the older population, vitamin D deficiency is a common cause of secondary hyperparathyroidism. Another cause is chronic kidney disease (CKD); these patients present with bone disease termed as osteodystrophy. It is also associated with cardiovascular disease and increased mortality. Treatment of secondary hyperparathyroidism is primarily medical using vitamin D supplements and calcium-based phosphate binders and calcimimetics. Dialysis is used for the management of acute nature. Tertiary hyperparathyroidism is usually a result of long-standing secondary hyperparathyroidism with autonomous parathyroid production. It can also occur with a few genetic diseases. Total parathyroid gland removal with autotransplantation in the forearm is the preferred management.