Hyperparathyroidism is caused by overactive parathyroid glands.
Overactive parathyroid glands produce high levels of parathyroid hormones, which, in turn, results in increased levels of calcium in the blood stream. Another result of hyperparathyroidism is kidney stones, because of high levels of calcium excreted into the urine by the kidneys. Hyperparathyroidism is quite rare in children. According to a recent study, children with hyperparathyroidism experience more severe symptoms than adults. The following are the most common symptoms of hyperparathyroidism in children.