Hyperparathyroidism

What is hyperparathyroidism?

Parathyroid glands are tiny glands located close to the thyroid gland. There are four parathyroid glands, which primarily function to regulate the calcium concentration in the blood. Hyperparathyroidism refers to over secretion of parathyroid hormone in the body due to one or more overactive parathyroid glands. This condition is more common among women aged 50 and above. The increased production of parathyroid hormone leads to an increase in calcium levels in the blood, which corresponds to decreased calcium concentration in the bones.

What are its main signs and symptoms?

• Mild hyperparathyroidism may be associated with the following symptoms:

1. Painful joints and bones
2. Weak muscles
3. Fatigue
4. Depression
5. Loss of appetite
6. Difficulty in concentration

●        Symptoms associated with severe hyperparathyroidism include:

1. Nausea and vomiting
2. Confusion
3. Excessive thirst and frequent urination

●        Other symptoms include:

1. Thinning bones (Osteoporosis)
2. Reduced kidney function
3. Kidney stones
4. High blood pressure

What are its main causes?

There are two types of hyperparathyroidism, namely:

• Primary hyperparathyroidism: In this condition, there is excessive secretion of parathyroid hormone because of one or more overactive parathyroid glands. The condition is termed ‘primary’ as the disorder originates in the parathyroid glands. A tumour or benign growth on the parathyroid gland can contribute to an excessive secretion of the hormone (Adenoma is the main cause of primary hyperparathyroidism in about 80% patients). Enlarged or hyperplastic parathyroid glands may also lead to parathormone overproduction.

• Secondary hyperparathyroidism: This occurs as a result of an underlying medical condition that can cause overactivation of parathyroid glands and over secretion of parathyroid hormone.

1. Kidney failure, where calcium levels in the blood are low.
2. Hereditary or genetic factors.
3. Vitamin D disorders.
4. Impaired absorption of food.

How is it diagnosed and treated?

Patient’s medical history and assessment of the associated symptoms guide the doctor about advising the necessary tests to diagnose hyperparathyroidism.

• Investigations include:
  1. Blood tests for assessing blood calcium and parathyroid hormone levels.
  2. Bone density scan called DEXA scan.
  3. CT scan and ultrasonography for detecting underlying kidney disease.
  4. Vitamin D levels.

Primary hyperthyroidism usually requires surgical treatment. Removal of the overactive parathyroid gland or a tumour has shown good results in cases of primary hyperparathyroidism.

• Surgical options include:
  1. Minimally invasive parathyroidectomy: Only the gland which is likely to be overactive is excised.
  2. Neck exploration: All four parathyroid glands are surgically explored and the overactive gland is excised.
• Mild hyperparathyroidism is monitored with blood tests and treatment is maintained with medications and vitamin D and calcium supplements. Diet, nutrition, and physical therapy also play a key role in controlling hyperparathyroidism.
• Secondary hyperparathyroidism requires treatment of the underlying condition. A group of drugs known as calcimimetics may be prescribed as adjunctive therapy.

1. Cleveland Clinic. [Internet]. Euclid Avenue, Cleveland, Ohio, United States; Hyperparathyroidism: Management and Treatment.
2. National Institute of Diabetes and Digestive and Kidney Diseases [internet]: US Department of Health and Human Services; Primary Hyperparathyroidism.
3. State of Victoria. [Internet]. Department of Health & Human Services. Parathyroid glands.
4. MedlinePlus Medical Encyclopedia: US National Library of Medicine; Hyperparathyroidism.
5. MedlinePlus Medical Encyclopedia: US National Library of Medicine; Parathyroid Disorders.