What are parathyroid glands?
Most people are oblivious of the existence of these small pea-shaped endocrine glands that are located behind the thyroid glands. Parathyroid glands are vital for most of the body’s core metabolism as they regulate the levels of calcium in the body.
There are four parathyroid glands and are located behind the neck, behind the thyroid glands. The hormone secreted by parathyroid glands (parathyroid hormone, PTH) controls and regulates calcium levels in blood, bones, and in the entire body.
All four parathyroid glands are the size of a pea, or a rice grain and are mustard yellow in color. In cases of parathyroid diseases, these glands tend to get inflamed. Parathyroid hormone released by the parathyroid glands influence organs like the kidneys, bones, and the small intestine.
When the levels of calcium are low in the body, the endocrine system senses this and prompts the parathyroid glands to release parathyroid hormone. With the release of parathyroid hormone, calcium from the bones is released into the bloodstream along with the production of vitamin D in the kidneys. This prompts more absorption of calcium in the small intestine thereby balancing the levels of calcium in the body.
When the calcium levels are high, the production and release of parathyroid hormone reduces in order to maintain normal levels of calcium in the body.
Importance of calcium in the body
Calcium is a vital element that is required for normal functioning of the body. Only the parathyroid glands regulate calcium levels in the body.
Some vital functions of calcium in the body:
- Calcium provides electrical energy to the muscles
- They strengthen bones
- Calcium is also responsible to provide electrical energy to the nervous system
Since the role of parathyroid glands is to regulate and redistribute calcium around the body, any parathyroid disorder leads to a change in the levels of calcium in the body. Changes in the levels of calcium lead to a variety of conditions by damaging the liver, arteries, kidneys, and the skeletal system. In fact, changes in the levels of calcium in the body can even lead to depression.
Normal serum calcium levels in the body
The levels of calcium in the body vary on numerous factors like age, gender, pregnancy, and the levels of vitamin D.
Normal calcium levels in males
- 1 to 14 years: 9.6 to 10.6 mg/dL
- 15 to 16 years: 9.5 to 10.5 mg/dL
- 17 to 18 years: 9.5 to 10.4 mg/dL
- 19 to 21 years: 9.3 to 10.3 mg/dL
- 22 and above: 8.9 to 10.1 mg/dL
Normal calcium in females
- 1 to 11 years: 9.6 to 10.6 mg/dL
- 12 to 14 years: 9.5 to 10.4 mg/dL
- 15 to 18 years: 9.1 to 10.3 mg/dL
- 19 and above: 8.9 to 10.1mg/dL
As the levels of calcium decreases, people feel symptoms like tingling sensation in fingers, dry skin, brittle nails, and muscle cramps (commonly in the back and legs). This condition is called hypocalcemia. In hypocalcemia, apart from physical symptoms, people even experience psychological symptoms. Symptoms of hypocalcemia include:
- Tingling sensation in tongue, lips, fingers, or feet
- Muscle pains
- Difficulty breathing
- Abnormal heartbeat
Low calcium levels are caused due to low levels of parathyroid hormone. This condition is called hypoparathyroidism.
Hypoparathyroidism is a rare condition that is caused due to low levels of parathyroid hormone production. With decreased parathyroid hormone, there is a decrease in the levels of calcium and an increase in the levels of phosphorus. Hypoparathyroidism can result either from a low production of parathyroid hormones or inadequate response of the bones and kidneys to the released parathyroid hormone.
Causes of Hypoparathyroidism
Hypoparathyroidism can be caused due to a few condition like:
- Surgical removal of parathyroid glands (parathyroidectomy)
- Congenital causes (congenital hypoparathyroidism)
- Autoimmune causes leading to acquired parathyroidism (when immune system attacks parathyroid gland tissues)
- Resistance by the bones and kidneys to respond to the released parathyroid hormone (Pseudo-hypoparathyroidism)
- Low levels of magnesium in the body
Treatment for hypoparathyroidism is provided by endocrinologists. This involves calcium and vitamin D supplementations.
Hyperparathyroidism is a condition that is characterized by higher levels of calcium in the body. High levels of calcium in the body is called hypercalcemia. Hyperparathyroidism increases the risk of having a heart disease, stroke, and even cancer.
With high levels of calcium (hypercalcemia) in hyperparathyroidism, there is an increased risk of kidney stones, weakened bones leading to osteoporosis, and other heart issues.
Complications of hyperparathyroidism
- Kidney stones
- Kidney failure
- Digestive issues like upset stomach, vomiting, and constipation
- Heart rhythm problems where the heartbeat gets irregular
- Nervous system problems like confusion, loss of memory (dementia), and even coma
- Bone problems like osteoporosis
While high levels of calcium can be caused due to a variety of reasons, having overactive parathyroid glands is a major reason.
Hyperparathyroidism is mainly caused due to tumors present in the parathyroid glands. They are diagnosed by measuring the calcium levels in the bloodstream, vitamin D levels, and the levels of parathyroid hormone (PTH). Other tests like bone mineral density, abdomen ultrasound, and urine tests are done in order to assess complications.
Treatment for hyperparathyroidism is done by a surgery called parathyroidectomy. This is a minimally invasive surgery done by endocrine surgeons. Medications for hyperparathyroidism include calcimimetics. Treatment is followed by vitamin D supplementation.