Which of the following is a common cause of hyperparathyroidism?
High-Yield Explanation
Primary hyperparathyroidism is caused by autonomous secretion of PTH, usually by a single parathyroid adenoma, which can vary in diameter from a few millimetres to several centimetres. It should be distinguished from secondary hyperparathyroidism, in which there is a physiological increase in PTH secretion to compensate for prolonged hypocalcaemia (such as in vitamin D deficiency), and from tertiary hyperparathyroidism, in which continuous stimulation of the parathyroids over a prolonged period of time results in adenoma formation and autonomous PTH secretion. This is most commonly seen in individuals with advanced chronic kidney disease.
The prevalence of primary hyperparathyroidism is about 1 in 800 and it is 2–3 times more common in women than men; 90% of patients are over 50 years of age. It also occurs in the familial MEN syndromes, in which case hyperplasia or multiple adenomas of all four parathyroid glands are more likely than a solitary adenoma.
Carcinomas of parathyroid glands are also associated with hyperparathyroidism.
Reference: : Davidson P R I N C I P L E S and Practice O F M E D I C I N E 23rd edition page no 663