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What is Hyperparathyroidism

​The parathyroid glands are four small glands, situated in the neck near the thyroid gland. The parathyroid glands secrete hormones to regulate the calcium levels of the body.


Hyperparathyroidism occurs when an excess of parathyroid hormone is released by the parathyroid glands into the blood. This leads to high levels of calcium in the blood.  

Types of hyperparathyroidism

  • Primary hyperparathyroidism is a condition caused by enlargement or hyperactivity of one or more of the parathyroid glands. The main cause of primary hyperparathyroidism is a non-cancerous) tumour called an adenoma of one of the four parathyroid glands,. This is uncommonly due to a disease of all the four glands (seen in families) and rarely due to parathyroid cancer.
  • Secondary hyperparathyroidism is most commonly caused by kidney failure, when the kidney is unable to absorb calcium and the body produces a large amount of parathyroid hormones to compensate this.
  • Tertiary hyperparathyroidism occurs in patients with chronic kidney disease when left untreated for a long period of time.
Signs & symptoms
  • ​Fatigue
  • Feelings of thirst and the frequent passage of urine
  • Feeling sick and losing your appetite
  • Muscle weakness or cramps
  • Constipation
  • Stomach pain or vomiting
  • Bone pain
  • Kidney stones
Diagnostic and treatment options

Test and diagnosis

A blood test will include measurement of the parathyroid hormone levels. The calcium and phosphate levels are also tested. Depending on the surgeon’s assessment, a special (MIBI) scan and/or an ultrasound examination of the neck is used to identify the location of the abnormal parathyroid glands.


Treatment of hyperparathyroidism depends on the cause of the condition.
Primary hyperparathyroidism will require removal of the abnormal parathyroid gland. This procedure can be performed under local or general anaesthesia. The removed specimen will be sent to the pathology department for evaluation. Following the removal of the abnormal gland, a blood test will be performed to check the level of parathyroid hormone to ascertain cure.  

Risks of parathyroidectomy

There are many potential risks involved in a parathyroidectomy surgery. It is important to realise that whilst some of these risks are serious, they are relatively rare. 

  • Bleeding:
As with any operation, there may be some bleeding from the site of the operation.

  •  Scarring:
The scar is usually sited within the skin crease. Most scars are more visible within the immediate post-operative period, but will be better camouflaged when the wound heals.

  • Damage to recurrent laryngeal nerve:
This nerve supplies the vocal cords. If one is damaged during the operation, the result may be a hoarse voice or a weak voice.

  • Low calcium:
There can be low calcium levels following removal of a hyperactive parathyroid gland after surgery. Patients may need to take supplemental oral calcium for a few days to several weeks following surgery.

  •  A second surgery:
If there are persistently high calcium levels in the blood, there may be remnant parathyroid tissue either in the neck or other areas of the body. Further investigations or a second procedure may be required to find and remove the remaining parathyroid glands.
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