The most common cause of hyperparathyroidism is: (A) Parathyroid adenoma, (B) Parathyroid hyperplasia, (C) MEN 1, (D) Medullary carcinoma of thyroid
Answer is A. Primary hyperparathyroidism is a generalized disorder of calcium, phosphate, and bone metabolism due to an increased secretion of PTH. The elevation of circulating hormone usually leads to hypercalcemia and hypophosphatemia.Solitary adenomas: A single abnormal gland is a cause in ~80% of patients; the abnormality in the gland is usually a benign neoplasmor adenoma and rarely a parathyroid carcinoma.Ref: Harrison; 19th edition; Page no: 2470