OverviewHyperparathyroidism is when your parathyroid glands create high amounts of parathyroid hormone in the bloodstream. These glands, located behind the thyroid at the bottom of your neck, are about the size of a grain of rice. Show
The parathyroid hormone produced by the thyroid glands helps maintain the right balance of calcium in the bloodstream and in tissues that depend on calcium for proper functioning. This is especially important for nerve and muscle function, as well as bone health. There are two types of hyperparathyroidism. In primary hyperparathyroidism, an enlargement of one or more of the parathyroid glands causes overproduction of parathyroid hormone. This causes high calcium levels in the blood, which can cause a variety of health problems. Surgery is the most common treatment for primary hyperparathyroidism. Secondary hyperparathyroidism occurs due to another disease that first causes low calcium levels in the body. Over time, increased parathyroid hormone levels occur as the body fights to keep the calcium level up in the standard range. This is common in kidney disease and after certain intestinal surgeries or diseases. SymptomsPrimary hyperparathyroidism is often diagnosed before signs or symptoms of the disorder occur. This is usually because an elevated level of calcium is found on routine blood tests. When symptoms do occur, they're the result of damage or dysfunction in other organs or tissues. This damage or dysfunction is due to high calcium levels in the blood and urine or too little calcium in bones. Symptoms may be so mild and nonspecific that they don't seem related to parathyroid function, or they may be severe. The range of signs and symptoms include:
When to see a doctorSee your health care provider if you have any signs or symptoms of hyperparathyroidism. These symptoms could be caused by many disorders, including some with serious complications. It's important to get a prompt, accurate diagnosis and the right treatment. Sign up for free, and stay up to date on research advancements, health tips and current health topics, like COVID-19, plus expertise on managing health. To provide you with the most relevant and helpful information, and understand which information is beneficial, we may combine your email and website usage
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Calcium is best known for its role in keeping your teeth and bones healthy. But calcium also aids in the transmission of signals in nerve cells. And it's involved in muscle contraction. Phosphorus, another mineral, works along with calcium in these areas. Sometimes one or more of the parathyroid glands produce high amounts of parathyroid hormone. These high hormone levels can be the body responding appropriately to keep the calcium in the standard range, or they may be inappropriately elevating the calcium in the blood. Which one depends on the underlying problem. Hyperparathyroidism may occur because of primary hyperparathyroidism or secondary hyperparathyroidism. Primary hyperparathyroidismPrimary hyperparathyroidism occurs because of a problem with one or more of the four parathyroid glands:
One or more of the parathyroid glands produces high amounts of parathyroid hormone. This leads to high calcium levels and low phosphorus levels in your blood. Primary hyperparathyroidism usually occurs randomly. But some people inherit a gene that causes the disorder. Secondary hyperparathyroidismSecondary hyperparathyroidism is the result of another condition that lowers the blood calcium, which then affects the gland's function. This causes your parathyroid glands to overwork and produce high amounts of parathyroid hormone to maintain or restore the calcium level to the standard range. Factors that may result in secondary hyperparathyroidism include:
Risk factorsYou may be at an increased risk of primary hyperparathyroidism if you:
ComplicationsComplications of hyperparathyroidism are mainly related to the long-term effect of too little calcium in your bones and too much calcium in your bloodstream. Common complications include:
Why is my PTH high but my calcium is normal?What if I have elevated parathyroid hormone (PTH) but normal calcium? Normal calcium levels despite high blood levels of parathyroid hormone could be a result of: Vitamin D deficiency. Very low amounts of dietary calcium over a long period of time.
Can you have hyperparathyroidism with normal vitamin D levels?A more recent study by our group in 25,000 patients showed 92% of patients with a parathyroid tumor and primary hyperparathyroidism have low Vitamin D-25. Less than 10% of all patients with primary hyperparathyroidism will have NORMAL Vitamin D-25 Levels (above 30).
Can you have high PTH and not have hyperparathyroidism?Primary Hyperparathyroidism
Some patients with a parathyroid tumor have normocalcemic hyperparathyroidism where the calcium level is normal but the PTH is high. Other patients may have high calcium but high-normal or normal PTH levels.
Does high PTH always mean hyperparathyroidism?Classically, if the calcium is high and the PTH is high at the same time, the diagnosis of hyperparathyroidism is made. Unfortunately, about 25 percent of people with a parathyroid tumor causing primary hyperparathyroidism will have high blood calcium but the PTH levels are normal.
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