There are four parathyroid glands in the neck. Two on either side behind the thyroid gland. The parathyroid glands release a hormone called parathyroid hormone (PTH). This hormone helps to control the levels of calcium and phosphorus in the body, which is useful for bone metabolism.

Parathyroid hormone also stimulates the kidneys to make an active form of vitamin D. Calcium phosphate gives hardness and strength to bones and teeth. Calcium and phosphorus are also needed for muscles, nerves and is useful in clotting mechanism.

Parathyroid gland can some time produce too much of parathormone (PTH). This condition is called hyperparathyroidism.

Hypoparathyroidism or reduced production of parathormone (PTH) is seen when:

• Parathyroid glands do not release enough parathyroid hormone, or
• Parathormone (PTH) that is released does not work properly.

The low level of active parathyroid hormone causes the calcium level in the blood to fall and the phosphate level to rise.

What are the causes for hypoparathyroidism?

Below are listed the reasons for hypoparathyroidism:

• Acquired hypoparathyroidism
• Transient hypoparathyroidism
• Congenital hypoparathyroidism
• Autoimmune hypoparathyroidism
• Pseudohypoparathyroidism
• Pseudopseudohypoparathyroidism

Acquired hypoparathyroidism is the commonest form, usually seen after surgery to the neck, radiotherapy and chemotherapy. Rarely cancer cells can damage all the parathyroid gland leading to  hypoparathyroidism. Usual neck surgeries include thyroid surgery and parathyroid surgery.

What are the symptoms of hypoparathyroidism?

Symptoms of hypoparathyroidism vary from person to person. Symptoms occur due to low blood levels of calcium. Severity of symptoms depend on the speed at which calcium levels drops in the blood.

Some of the symptoms that may occur due to low calcium include:

• Tingling, burning or numbness of the fingers, face and toes
• Twitching of the muscles
• Tightening, of the muscles of the hands and feet
• Fits or seizures
• Dizziness
• Confusion
• Memory problems
• Tiredness
• Headaches and Muscle pain
• Brittle nails
• Dry skin
• Abdominal pain

What can happen if hypoparathyroidism is not treated?

Several complications are encountered if hypoparathyroidism is not adequately treated. Not treating very low calcium is life threatening.

When hypoparathyroidism is not treated adequately complications due to low calcium levels can lead to the following conditions:

• Cataract
• Kidney stones
• Depression
• Osteoporosis
• Mood changes
• Aches and pain
• Irregular heart rhythm
• Stunted growth in children
• Slow mental development

How is hypoparathyroidism diagnosed?

Following a detailed history and physical examination, endocrinologist will arrange a number of blood tests, scans, x-rays and for some people genetic tests (if hypoparathyroidism is considered hereditary) will be arranged.

What are treatment options available for hypoparathyroidism?

Treatment for hypoparathyroidism is aimed at correcting low calcium levels. Prevention for hypoparathyroidism is important. It is advisable to let your close family and friends know about this condition and wear a medical alert bracelet. This will help prompt treatment in the event of an emergency.

Treatment for hypoparathyroidism is usually lifelong and you will need regular monitoring. You may need more frequent monitoring of blood calcium levels if you are unwell or pregnant.

Hypoparathyroidism is treated with oral calcium and vitamin D supplements. Calcium levels in the blood should be checked at regular intervals to ensure you are on the correct dose of supplements.

If symptoms are severe or you are unable to take calcium tablets or not able to absorb oral calcium and vitamin D supplements, intravenous calcium is given.

Whilst you need to take calcium and vitamin D supplements regularly, a balanced meal rich in calcium and vitamin D is advisable.

If the recommended dose of calcium and vitamin D supplements are taken regularly, long term prognosis of hypoparathyroidism is usually good.

In some people who are resistant to treatment, more investigations and newer medications can be considered.

Dr Chinnadorai Rajeswaran is a consultant Physician specialising in Endocrinology, Diabetes and Obesity. As a private endocrinologist he  has private endocrine, diabetes and weight loss clinics in Harley Street, London, Chennai (India), Claremont Hospital, Sheffield, Nuffield Hospital, Leeds and Simplyweight, Bradford.

He has face to face consultations with people from Barnsley, Rotherham, Chesterfield, Doncaster, Wakefield, Huddersfield, Bradford, Harrogate, Leeds, Sheffield, London and Chennai (India). He also offers video consultations.