Hypoparathyroidism
Hypoparathyroidism is a rare condition where the body doesn’t make enough parathyroid hormone, leading to low calcium levels in the blood. While most cases occur after neck surgery, this treatable condition can be managed with proper care and supplements.
Table of contents
What is hypoparathyroidism
Hypoparathyroidism is a rare condition that happens when small glands in your neck called parathyroid glands don’t produce enough parathyroid hormone (PTH)[1]. There are four tiny parathyroid glands located in the neck near the thyroid gland[1].
Parathyroid hormone plays a key role in controlling and maintaining the right balance of two important minerals in the body: calcium and phosphorus[1]. When the body doesn’t make enough of this hormone, it leads to unusually low levels of calcium in the blood and high levels of phosphorus[1].
Calcium is one of the most important minerals in your body. Most of your calcium is stored in your bones, but you also need it in your blood. The calcium in your blood helps your nerves work, your muscles contract so you can move, your blood clot, your heart work properly, and your bones stay strong[8]. Low calcium levels in your blood can affect how well your body works[8].
Causes and risk factors
The most common cause of hypoparathyroidism is damage to the parathyroid glands during surgery. About 75% of cases are caused by accidental damage to the parathyroid glands during neck or thyroid surgery[8]. This is the most common reason, with unintended removal or injury during head and neck surgery being responsible for most cases[2]. This usually happens soon after surgery, but it can also occur many years later[8]. In rare cases, radiation therapy can damage your parathyroid glands[8].
Other causes of hypoparathyroidism include[3]:
- A baby born without parathyroid glands, with underdeveloped parathyroid glands, or with the inability to make or use the parathyroid hormone
- Autoimmune disorders that damage or destroy the parathyroid glands
- Certain genetic conditions
Less than 10% of cases are genetic. The most common genetic condition is DiGeorge syndrome, where babies are born without parathyroid glands, leading to lifelong low calcium[8]. About 60% of children with hypoparathyroidism have DiGeorge syndrome[8].
Low levels of magnesium can also cause hypoparathyroidism. Low magnesium can cause the parathyroid glands to stop making or releasing enough parathyroid hormone, leading to low calcium levels[8]. In some cases, the cause is unknown[3].
Risk factors for hypoparathyroidism include having recent neck or thyroid surgery, having a family history of parathyroid conditions, having an autoimmune disease that affects your endocrine system, having radiation therapy for head or neck cancer, or being born prematurely[3][8].
Both adults and children can get hypoparathyroidism. Adults are more likely to get hypoparathyroidism from accidental damage to their parathyroid glands during surgery. Children are more likely to have hypoparathyroidism due to a genetic condition[8].
Symptoms
Symptoms of hypoparathyroidism are often related to low calcium levels in the blood[1]. Symptom severity varies depending on the calcium level and duration of parathyroid dysfunction[2]. In most cases, hypoparathyroidism progresses gradually, and symptoms can be mild. Many people have symptoms for years before they get a diagnosis[8].
Common symptoms include[1][3][8]:
- Tingling or burning sensation in the fingers, toes and lips
- Muscle aches or cramps in the legs, feet, stomach or face
- Twitching or spasms of muscles, mainly around the mouth but also in the hands, arms and throat
- Numbness around the mouth or in hands or feet
- Tiredness or weakness
- Headaches
- Trouble with memory or “brain fog”
The most common symptom is muscle cramps or tightness and tingling of the lips or fingers. This condition is known as tetany, which causes twitching and painful spasms in muscles of the face, hands, arms, throat and, sometimes, the feet[5].
Other symptoms can include[3][8]:
- Coarse, brittle hair, and dry skin
- Brittle nails
- Cataracts (cloudy patches that form at the front of your eyes)
- Dental problems
- Weak tooth enamel (in children)
Less common and more serious symptoms include confusion, an irregular heartbeat, seizures (fits), unstable emotions, anxiety, or depression[3][12]. Cardiac symptoms associated with conditions such as acute cardiomyopathy and congestive heart failure that result from impaired contractility secondary to low calcium may also occur[2].
You should see a doctor if you think you might have symptoms of hypoparathyroidism[1]. Call your healthcare professional right away if you have a seizure or trouble breathing, as hypoparathyroidism can lead to either of these medical problems[1].
Diagnosis
Hypoparathyroidism is typically diagnosed with laboratory studies[2]. To find out if you have hypoparathyroidism, your healthcare professional may start by asking you about your medical history. You’re also given a physical exam[4].
If there’s a chance you have hypoparathyroidism, you may have a number of blood tests to measure how much calcium is in your blood and to rule out other possible causes of your symptoms[12]. A low level of calcium can be a sign of hypoparathyroidism[12].
The following blood test results might suggest hypoparathyroidism[4]:
- A low level of calcium in the blood
- A low level of parathyroid hormones
- A high level of phosphorus in the blood
Hypoparathyroidism is typically diagnosed with laboratory studies confirming a low corrected calcium level as well as a decreased or undetectable parathyroid hormone level[2]. The level of magnesium in your blood also might be checked. A low level of magnesium may cause a low blood-calcium level[4].
Your doctor will also do a blood test to measure levels of calcium, phosphorus, magnesium, and parathyroid hormone. You also might have a urine test to show how much calcium you are losing in your urine[5]. Parathyroid hormones act on the kidneys to prevent too much calcium from going into the urine. A urine test can tell whether your body is getting rid of too much calcium[4].
Your healthcare professional may suggest more tests. These might include other blood tests or a test to check your heart’s rhythm, called an electrocardiogram[4].
If you’re having neck or head surgery, you may have these tests soon after surgery. This is used to check if there was any damage to your parathyroid glands[12].
Treatment
Treatment of patients with hypoparathyroidism involves correcting the low calcium by administering calcium and vitamin D[11]. Hypoparathyroidism treatment aims to ease symptoms and bring calcium and phosphorus levels in your body back into healthy ranges[4].
Hypoparathyroidism can be treated by taking[12]:
- Calcium supplements – to raise the level of calcium in your body
- Vitamin D supplements – vitamin D helps your body make better use of calcium
You’ll usually need to take supplements for the rest of your life[12]. Depending on the cause of hypoparathyroidism, you’ll likely need to take supplements for the rest of your life[1].
Treatment may include[4]:
- Oral calcium. These calcium supplements are taken by mouth as tablets, chews or liquid. They can raise calcium levels in your blood. In high amounts, they can cause side effects such as constipation in some people.
- Vitamin D. High amounts of vitamin D can help your body absorb calcium and get rid of phosphorus. Often, this vitamin D is a prescription supplement called calcitriol. It’s different from the usual supplements you can get without a prescription.
- Magnesium. If your magnesium level is low and you have symptoms of hypoparathyroidism, you may need to take a magnesium supplement.
- Thiazide diuretics. These medicines may be used if your calcium levels stay low even with treatment.
Your child may need to see a pediatric endocrinologist. This is a doctor who specializes in treating children with hormone problems[3]. Treatment may include calcium given through an IV or through the mouth. This can give relief of symptoms right away. Your child may also need to take vitamin D, magnesium supplements, or other treatments[3].
You may be offered supplements even if you do not have any symptoms, but tests show damage to your parathyroid glands. This helps lower the risk of any serious problems[12].
You may also be advised to make some changes to your diet, such as eating foods high in calcium, such as dairy products, green leafy vegetables, soy and tofu, and avoiding or cutting down on red meat and starchy foods, like pasta and white bread[12].
You’ll need regular blood tests to check your calcium levels. If these tests show supplements are not working well, then you may need extra medicines[12].
Within the last several years, recombinant human parathyroid hormone became available and is currently used as replacement therapy in patients unresponsive to supplementation[2]. Palopegteriparatide is a prodrug of the parathyroid hormone analog and is commercially available in the United States for treatment of hypoparathyroidism in adults. It is administered as a subcutaneous injection given once daily[11].
Palopegteriparatide is a prodrug with sustained release designed to provide stable physiological parathyroid hormone levels for 24 hours a day[10]. A phase 3 study demonstrated maintenance of normal calcium levels in patients with chronic hypoparathyroidism, with no need for conventional therapy. Furthermore, this treatment lowers urinary calcium and improves quality of life[10].
Complications
The most common complications of hypoparathyroidism are chronic kidney disease and kidney stones[2]. Other complications include cataracts, cognitive dysfunction, cardiac arrhythmias, anxiety, and depression[2].
Long-term complications of hypoparathyroidism can include issues with kidney function, kidney stones, and calcium deposits in your brain[8].
For children, complications from hypoparathyroidism can include slow growth, dental issues, developmental delays, and bone problems[8].
Complications of a sudden drop in calcium levels include seizures and larynx spasms. These can be dangerous. If you’re experiencing these symptoms, get to the nearest hospital as soon as possible[8].
If you have hypoparathyroidism and your calcium level becomes too low, it can cause seizures and serious heart problems. If this happens, you’ll need to be treated in hospital. You’ll be given calcium through a tube into a vein, until your calcium level returns to normal[12].
If you have hypoparathyroidism, health professionals will be there to support you throughout your treatment. You can also get information and support from Parathyroid UK, a UK charity for people living with parathyroid conditions[12].
