The Parathyroids

 

The Parathyroids

 

What are the parathyroid glands?

The parathyroid glands are very small glands (about the size of a grain of rice) situated in the neck just behind the thyroid gland.  There are usually four parathyroid glands – two on each lobe of the thyroid gland – which produce a hormone called parathyroid hormone.1

 

What do they do?

The parathyroid glands control calcium levels in the bloodstream to make sure you don’t have too little or too much calcium.

If calcium levels drop, the parathyroid glands release parathyroid hormone into the blood which then causes the bones to release calcium.  Parathyroid hormone also causes the kidneys to stop releasing calcium into the urine and stimulates the kidneys to increase vitamin D metabolism. The vitamin D then increases calcium absorption from the gut.

If calcium or vitamin D levels are low, the parathyroid glands produce more parathyroid hormone to bring levels up to normal.1

 

Primary hyperparathyroidism

The most common form of hyperparathyroidism (and the third most common endocrine disorder in men and women)2 is called primary hyperparathyroidism.   Similar to hypothyroidism, it is more common in women, and most commonly seen in women aged 50-60.3

The parathyroid glands can make too much parathyroid hormone hyperparathyroidism.  This causes high calcium levels (hypercalcaemia).1

 

What causes primary hyperparathyroidism?

In 75-85% of cases the cause is a single benign (non-cancerous) growth or nodule (adenoma) in one gland.  Growths in more than one gland are not very common and cancer in the parathyroid glands is very rare (less than 1%).2

In rare cases, primary hyperparathyroidism can have genetic causes.

 

What are the symptoms of hyperparathyroidism?

Some people have no symptoms1,2,3 and the condition is found via a routine blood test.  Symptoms can vary depending on the length of time you have had the problem:

  • increased thirst
  • increased urine production
  • abdominal pain
  • constipation
  • aches and pains
  • mood changes
  • nausea
  • loss of appetite
  • tiredness
  • poor concentration
  • confusion
  • depression

It may take some time for hyperparathyroidism to be diagnosed because the symptoms are similar to symptoms of other conditions so other potential causes need to be excluded.

If the condition has gone on a long time undetected, calcium in the bones can be lost to the blood and urine hence high blood and urine levels of calcium.  This can eventually cause osteoporosis, calcium stones in the kidneys, peptic ulcers and pancreatitis (inflammation of the pancreas).

This can then cause further symptoms:3

  • vomiting
  • drowsiness
  • dehydration
  • muscle spasms
  • bone pain or tenderness
  • joint pain
  • irregular heartbeat
  • high blood pressure (hypertension)

In very severe cases hyperparathyroidism can cause the high calcium levels to lead to:

  • kidney failure
  • loss of consciousness
  • coma
  • heart rhythm abnormalities

 

How is it diagnosed?

It is important that hyperparathyroidism is diagnosed quickly.  It is diagnosed by looking at calcium and parathyroid hormone levels in the blood and urine. Phosphorus levels can also be checked for low levels.

It is also recommended to have a bone density scan (DEXA), X-rays, CT scans or ultrasound scans of the kidneys to check for osteoporosis and kidney stones.

 

How is hyperparathyroidism treated?

Depending on the severity of the condition, conservative management only may be required, or another option is to remove the affected parathyroid gland/s.1,2 Medication may be given to lower calcium levels as a short-term treatment to stabilise levels.

 

Secondary hyperparathyroidism

Secondary hyperparathyroidism is due to a condition outside of the glands such as kidney failure or vitamin D deficiency which lowers calcium levels which in turn causes the parathyroid glands to make extra parathyroid hormone.3

Treatment for secondary hyperparathyroidism depends on whether it is caused by vitamin D deficiency or kidney disease.

Vitamin D deficiency is treated with oral vitamin D.3

 

Tertiary hyperparathyroidism

This is long-standing secondary hyperparathyroidism usually associated with very advanced kidney failure.3

 

Hypoparathyroidism

Another condition can be caused when the parathyroid glands do not produce enough parathyroid hormone – hypoparathyroidism.   This causes low blood calcium levels (hypocalcaemia).1

This can happen after neck surgery such as a thyroidectomy.

 

What are the symptoms of hypoparathyroidism?

The main symptoms1 of hypoparathyroidism are:

  • tingling
  • pins and needle sensations
  • muscle cramps/spasms

 

How is it diagnosed?

Hypoparathyroidism is diagnosed by looking at calcium and parathyroid hormone levels in the blood and urine.

 

How is hypoparathyroidism treated?

Treatment includes vitamin D or calcium supplementation.1

 

Prognosis

The prognosis of treating conditions of the parathyroid gland depends on the cause of the condition.

If you have mild hyperparathyroidism, not needing surgery, you may not develop any problems or need any treatment in the future.  However, some people will find that their calcium levels will slowly rise so you may need further treatment.

If you have had surgery and it was successful, things should return to normal although some generalised symptoms may remain such as fatigue.2

If you have hyperparathyroidism, you need to ensure that you eat a healthy, balanced diet.  There is no need to avoid calcium as this may cause osteoporosis although you should avoid a high-calcium diet and avoid becoming dehydrated.3

 

Check out what people are saying on our online community about parathyroids: 

http://www.healthunlocked.com/thyroiduk

 

Thyroid UK relies on donations so that we can continue to support and campaign for people with thyroid disease and related disorders.  If you have found our information helpful, please do think about donating or becoming a member.

 

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Further information:

Parathyroid UK – https://parathyroiduk.org/

 

Glossary

Calcium – is a mineral found in many foods. The body needs calcium to maintain strong bones and to carry out many important functions. Almost all calcium is stored in bones and teeth, where it supports their structure and hardness

Endocrine – relating to glands which secrete hormones or other products directly into the blood

Genetic – relating to genes or heredity

Hyperparathyroidism – a condition in which one or more of the parathyroid glands become overactive and secrete too much parathyroid hormone (PTH)

Hypocalcemia – low calcium levels in the blood serum

Hypoparathyroidism – a condition in which one or more of the parathyroid glands become underactive and secrete too little parathyroid hormone (PTH)

Kidney – a pair of organs in the abdominal cavity that excrete urine

Metabolism – the chemical processes within the human body

Nodule – a growth of abnormal tissue

Osteoporosis – medical condition in which the bones become brittle and fragile from loss of tissue, typically as a result of hormonal changes, or deficiency of calcium or vitamin D

Pancreas – a large gland behind the stomach, which secretes digestive enzymes into the duodenum (the first part of the small intestine)

Parathyroid glands – four small pea-sized glands located in the neck just behind the thyroid gland which control calcium levels in the bloodstream

Parathyroid hormone – parathyroid hormone (PTH) is a hormone secreted by the parathyroid glands that regulates the serum calcium through its effects on bone, kidney, and intestine

Peptic ulcers – open sores that develop on the inside lining of the stomach and the upper portion of the small intestine

Phosphorus – a mineral that makes up 1% of a person’s total body weight. It is the second most abundant mineral in the body. It is present in every cell of the body and most of it is found in the bones and teeth

Thyroidectomy – the removal of all (total) or part (partial) of the thyroid gland

Ultrasound – sound or other vibrations having an ultrasonic frequency, particularly as used in medical imaging

 

References

1. You and Your Hormones
Parathyroid Glands
https://www.yourhormones.info/glands/parathyroid-glands/

2. You and Your Hormones
Primary Hyperparathyroidism
https://www.yourhormones.info/endocrine-conditions/primary-hyperparathyroidism/

3. NHS
Hyperparathyroidism
https://www.nhs.uk/conditions/hyperparathyroidism/

 

Date created: 17/12/19 (V1.4)
Review date: 17/12/21