hormonal and metabolic disorders
Hypercalcemia (High Level of Calcium in the Blood)
Causes of Hypercalcemia
Causes of hypercalcemia include the following: Hyperparathyroidism:One or more of the four parathyroid glands secrete too muchparathyroid hormone, which helps control the amount ofcalciumin blood. Occasionally, hypercalcemia develops in people with Peptic Ulcer Disease if they drink a lot of milk and take calcium-containing antacids for relief of the ulcer pain. The resulting disorder is called the milk-alkali syndrome. Too muchvitamin Dintake:If people take very high daily doses ofvitamin Dover several months, the amount ofcalciumabsorbed from the digestive tract increases substantially. level in blood. These effects, called humoral hypercalcemia of malignancy, are considered a Paraneoplastic Syndromes . is released into the blood, sometimes causing hypercalcemia. In Paget Disease of Bone , bone is broken down, but the Inactivity:Rarely, people who are immobilized, such as those who are paralyzed, or people who must remain in bed for a long time, develop hypercalcemia because calcium in bone is released into the blood when bones do not bear weight for long periods of time. Granulomatous disorders, such as Sarcoidosis , Lack of mobility can make thecalciumlevel high because bones weaken and releasecalciuminto the blood. (See also Hyperparathyroidism .) The parathyroid glands releaseparathyroid hormone, which Increases the absorption ofcalciumfrom the digestive tract Causes the kidneys to excrete lesscalcium Causes bones to release storedcalcium Parathyroid hormonecauses the kidneys to excrete more phosphate, but it also causes the bones to release phosphate into the blood. The balance between these two effects determines whether the phosphate level remains normal or decreases. If the parathyroid glands release too muchparathyroid hormone, hyperparathyroidism results. People with hyperparathyroidism have too muchcalciumand a normal or low level of phosphate in their blood. In primary hyperparathyroidism, an abnormality causes the release of too muchparathyroid hormone. In about 90% of people with primary hyperparathyroidism, the abnormality is a noncancerous tumor (adenoma) in one of the parathyroid glands. In the remaining 10%, the glands simply enlarge and produce too much hormone. Rarely, cancers of the parathyroid glands cause hyperparathyroidism. Primary hyperparathyroidism is more common among women than among men. It is more likely to develop in older adults and in people who have received radiation therapy to the neck. Sometimes it occurs as part of the syndrome of , a rare hereditary disorder. Primary hyperparathyroidism is usually treated by surgically removing one or more of the parathyroid glands. The goal is to remove all parathyroid tissue that is producing excess hormone. Surgery is successful in almost 90% of cases. level in blood, as can occur in Chronic Kidney Disease and Treatment depends on the cause. In tertiary hyperparathyroidism, excessparathyroid hormoneis released regardless of the amount ofcalciumin the blood. Tertiary hyperparathyroidism usually occurs in people who have had long-standing secondary hyperparathyroidism. Treatment depends on the cause. The syndrome of familial hypocalciuric hypercalcemia is a hereditary disorder that results from the parathyroid glands underestimating the amount ofcalciumin the blood and, in response, mistakenly secreting too muchparathyroid hormone. Parathyroid surgery is not useful in this disorder, and other treatment is usually not needed. 