What causes hyperparathyroidism?In most cases doctors don't know the cause. The vast majority of cases occur in people with no family history of the disorder. Only about 3 to 5 percent of cases can be linked to an inherited problem. Familial endocrine neoplasia type I is one rare inherited syndrome that affects the parathyroids as well as the pancreas and the pituitary gland. Another rare genetic disorder, familial hypocalciuric hypercalcemia, is sometimes confused with typical hyperparathyroidism.
Patients may believe they have felt fine, but realize improvements in sleep, irritability, and memory following treatment. When symptoms are present, they may include development of gastric ulcers or pancreatitis because high calcium levels can cause inflammation and pain in the linings of the stomach and pancreas. Causes of hyperparathyroidism also include benign (non-cancerous) tumors on the parathyroid glands or enlargement of the parathyroid glands.