Hypoparathyroidism

What is hypoparathyroidism?

Hypoparathyroidism is a rare, treatable condition that happens when you have low levels of parathyroid hormone in your blood, which causes you to have low levels of calcium (hypocalcemia) and high levels of phosphorous in your blood.

Hypoparathyroidism is usually a chronic (lifelong) condition, but it can be temporary.

What are parathyroid glands?

Most people have four pea-sized parathyroid glands located behind their thyroid gland — the butterfly-shaped gland in your neck. Like your thyroid, your parathyroid glands are part of your endocrine system. Sometimes your parathyroid glands are located along your esophagus or in your chest. These are known as ectopic (in an abnormal place) parathyroid glands.

Your parathyroid glands are in charge of controlling the amount of calcium in your blood by producing parathyroid hormone (PTH). Too little PTH results in low amounts of calcium in your blood (hypocalcemia), and too much PTH causes high amounts of calcium in your blood (hypercalcemia). PTH also helps control the levels of phosphorus and vitamin D in your blood and bones.

What is calcium and what does it do?

Calcium is one of the most important and common minerals in your body. Most of your calcium is stored in your bones, but you have and need it in your blood as well. The calcium in your blood has many important roles, including helping:

• Your nerves work.
• Make your muscles squeeze together so you can move.
• Your blood clot if you’re bleeding.
• Your heart work properly.

A low level of calcium in your blood (hypocalcemia), which is caused by hypoparathyroidism, can affect your body’s ability to perform these important functions. Your body also needs calcium in your bones to make them strong. Hypocalcemia happens when there are low levels of calcium in your blood, not in your bones.

Can hypoparathyroidism cause an electrolyte imbalance?

Calcium and phosphorus are both electrolytes. Hypoparathyroidism can lead to electrolyte imbalance since it causes low levels of calcium and high levels of phosphorous in your blood.

Electrolytes are essential minerals in your body that have an electric charge. They’re key to many important functions in your body. Because of this, it’s important to treat hypoparathyroidism to return your blood calcium and phosphorus levels to normal.

Low levels of magnesium, another important electrolyte, can also cause hypoparathyroidism because your parathyroid glands need magnesium to function properly.

What is the difference between hypoparathyroidism and hyperparathyroidism?

In the medical world, the prefix “hyper-” means “too much” or “high.” The prefix “hypo-” means “not enough” or “low.” Hypoparathyroidism happens when your parathyroid glands don’t release enough parathyroid hormone (PTH), and hyperparathyroidism happens when your parathyroid glands make too much PTH.

Since your parathyroid glands are in charge of controlling the amount of calcium in your blood, too much PTH causes too much calcium in your blood, and too little PTH causes not enough calcium.

Who gets hypoparathyroidism?

Both adults and children can get hypoparathyroidism, though it’s a rare condition. Adults are more likely to get hypoparathyroidism from accidental damage to their parathyroid glands from neck or thyroid surgery. Children are more likely to have hypoparathyroidism due to a genetic condition called DiGeorge syndrome.

How common is hypoparathyroidism?

Hypoparathyroidism is a rare condition. It affects fewer than 200,000 people in the United States.

What causes hypoparathyroidism?

Causes of hypoparathyroidism include:

• Damage to your parathyroid glands: Approximately 75% of hypoparathyroidism cases are from accidental damage to your parathyroid glands from neck or thyroid surgery. Hypoparathyroidism can occur years to decades after you’ve had thyroid or neck surgery, but it’s more likely to develop soon after surgery. Most of these cases of hypoparathyroidism are temporary, but some are chronic. Your parathyroid glands can also be damaged from radiation therapy, though this is rare.
• Certain genetic conditions: Genetic causes of hypoparathyroidism represent fewer than 10% of cases. The most common genetic cause is DiGeorge syndrome, a chromosomal genetic condition. A baby born with DiGeorge syndrome doesn’t have parathyroid glands. Without parathyroid glands, your body can’t make parathyroid hormone, so people with DiGeorge syndrome have chronic hypoparathyroidism. Approximately 60% of children who have hypoparathyroidism have DiGeorge syndrome. Other genetic syndromes that are associated with deafness and kidney disease can also cause hypoparathyroidism.
• Certain autoimmune diseases: A disease called type 1 autoimmune polyglandular syndrome causes your immune system to attack your parathyroid glands, which causes chronic hypoparathyroidism. Addison’s disease and pernicious anemia can also cause hypoparathyroidism.
• Infiltrative disorders: Your parathyroid glands can be infiltrated (invaded) by iron (hemochromatosis), copper (Wilson disease) and certain cancer metastases. Each of these situations can cause hypoparathyroidism.
• Low levels of magnesium: Your parathyroid glands need magnesium, a type of electrolyte in your blood, to function properly. Because of this, low levels of magnesium (hypomagnesemia) can cause hypoparathyroidism. This is often called functional hypoparathyroidism because the hypoparathyroidism goes away when appropriate levels of magnesium are restored.

What are the signs and symptoms of hypoparathyroidism?

In most cases, hypoparathyroidism progresses very gradually, and symptoms can be mild. Many people have symptoms for years before they’re diagnosed.

Signs and symptoms of hypoparathyroidism include:

• Tingling in your lips, fingers and toes.
• Muscle cramps.
• Muscle spasms (tetany).
• Abdominal pain.
• “Brain fog” or confusion.
• Abnormal heart rhythm (arrhythmia).
• Brittle nails.
• Dry hair and dry, scaly skin.
• Cataracts.
• Weakened tooth enamel (in children).

How is hypoparathyroidism diagnosed?

Hypoparathyroidism is generally diagnosed when a person has low levels of calcium and parathyroid hormone in their blood.

Since symptoms are often mild, healthcare providers sometimes “accidentally” find hypoparathyroidism when a routine blood screening shows the person has low levels of blood calcium.

A person is considered to have chronic hypoparathyroidism if they have low blood levels of parathyroid hormone and calcium at least twice within six months.

What tests are used to diagnose hypoparathyroidism?

If you’re experiencing symptoms of hypoparathyroidism, your healthcare provider will perform a physical exam and ask questions about your symptoms and medical history.

They may have you undergo one or more of the following tests, which can help diagnose hypoparathyroidism:

• Parathyroid hormone (PTH) blood test.
• Calcium blood test.
• Phosphorus blood test.
• Magnesium blood test.
• 24-hour urine test.

Your healthcare provider may have you undergo other tests to check for more serious side effects of hypoparathyroidism, including:

• An electrocardiogram (ECG or EKG) to check for an abnormal heart rhythm.
• A computed tomography (CT) scan to check for calcium deposits in your brain.

How is hypoparathyroidism treated?

The goal of treatment for hypoparathyroidism is to minimize symptoms and correct the amount of calcium and minerals in your body.

Treatment can include:

• Taking calcium carbonate and vitamin D supplements: Most people with hypoparathyroidism have to take calcium and vitamin D supplements for life. It’s the go-to treatment option for hypoparathyroidism. Your body needs vitamin D to absorb and use calcium, so if you have hypoparathyroidism, you need to take both supplements.
• Eating a high-calcium and low-phosphorous diet: People with hypoparathyroidism likely won’t get enough calcium that they need from diet alone, but your healthcare provider may recommend eating a diet high in calcium and low in phosphorous if you have hypoparathyroidism.
• Getting parathyroid hormone (PTH) injections: If taking calcium and vitamin D supplements isn’t working to treat your hypoparathyroidism, your provider might have you take parathyroid hormone injections.

Are there any side effects to hypoparathyroidism treatment?

If a person with hypoparathyroidism has too much vitamin D and calcium as a part of their treatment, it can cause a high level of blood calcium (hypercalcemia), which can be harmful to your health. Because of this, you’ll have to have your blood monitored frequently to make sure your hypoparathyroidism treatment is working properly.

Long-term use of parathyroid hormone injections may cause osteosarcoma, a type of bone cancer. For this reason, healthcare providers don’t generally prescribe it to treat hypoparathyroidism unless it’s absolutely necessary.

What are the risk factors for hypoparathyroidism?

Risk factors for hypoparathyroidism include:

• Having recent neck or thyroid surgery.
• Having a family history of parathyroid conditions.
• Having certain autoimmune diseases that affect your endocrine system, such as Addison’s disease.

What is the outlook (prognosis) for hypoparathyroidism?

The prognosis for hypoparathyroidism is generally good, especially if it’s diagnosed early.

However, if a person has cataracts, brain calcifications and/or dental changes from hypoparathyroidism, they can’t be reversed.

How long does hypoparathyroidism last?

Most cases of hypoparathyroidism are chronic (life-long), though it can sometimes be temporary.

Are there complications of hypoparathyroidism?

Long-term complications of hypoparathyroidism can include:

• Issues with kidney function.
• Kidney stones.
• Cataracts.
• Calcium deposits in your brain.

For children specifically, complications from hypoparathyroidism can include:

• Poor growth.
• Dental issues.
• Slow mental development.

Complications of untreated hypoparathyroidism due to sudden and severe (acute) hypocalcemia include seizures and larynx spasms, which can make it difficult to breathe. If you’re experiencing these symptoms, get to the nearest hospital as soon as possible.

When should I see my healthcare provider?

If you experience symptoms of hypoparathyroidism, contact your healthcare provider.

If you’ve already been diagnosed with hypoparathyroidism, you’ll need to see your provider regularly to monitor your blood calcium levels to make sure your treatment is working.

If you have symptoms of acute hypocalcemia, such as painful muscle cramps or seizures, get to the nearest hospital as soon as possible.

A note from Cleveland Clinic

Hypoparathyroidism is a rare condition. The good news is that it’s treatable. Symptoms of hypoparathyroidism can be mild and undetectable, so it’s important to let your healthcare provider know if you have risk factors for hypoparathyroidism such as having a family history of parathyroid conditions or having had neck or thyroid surgery. Your provider can run some simple blood tests to make sure your parathyroid hormone and calcium levels are where they should be.