Hyperparathyroidism Wheeless

Description: a disorder which is caused by excessive production of parathyroid hormone which leads to hypercalcemia, recurrent nephrolithiasis, pancreatitis, peptic ulcers, and mental changes; - incidence of approx 5 /10,000 pts per year; - usually affects adults over 50 yrs & occurs more commonly in females; - causes: - in most cases is due to single parathyroid adenoma (80% of patients); - malignant tumor: occurs in about 1% of patients with hyperparathyroidism; - occurs often in association w/ multiple endocrine neoplasia syndrome, and rarely to parathyroid carcinoma; - hyperparathyoidism is sometimes seen in renal cell carcinoma and squamous cell carcinoma; - diff dx: - occult tumor; - multiple myeloma (often associated w/ hypercalcemia); - classification: - primary defect of the parathyroid gland w/ hypersecretion of PTH as seen w/ adenoma's of the parathyroid gland; - secondaray causes arise from conditions that produces abnormally low ionic plasma Ca levels and thereby stimulates production of PTH (see renal disease: effects on bone): - tertiary conditions in which PTH secretion has become autonomous after prolonged stimulation of gland owing to secondary parathyroidism;