Parathyroid glands are tiny glands located next to the thyroid.
Hyperparathyroidism is a disorder of the parathyroid glands, resulting in hyper-functioning, or excessive secretion of parathyroid hormones (PTH), which in turn stimulates increased levels of calcium in the bloodstream. Calcium plays an important role in bone development, maintaining bone strength, nerve transmission and muscle contraction.
When there is a benign tumor in a parathyroid gland, the condition is called a parathyroid adenoma, which usually results in hypercalcemia – condition of excessive accumulation of calcium in the blood. When more than one parathyroid gland becomes enlarged, the condition is called parathyroid hyperplasia. Both of these conditions are benign (non-cancerous). Less than 1 % of people may have cancer of the parathyroid gland.
What is primary hyperparathyroidism?
Primary hyperparathyroidism is a metabolic disorder in which one (or more) of the parathyroid glands produces too much parathyroid hormone, which can result in the loss of bone tissue. A function of the parathyroid hormone is to keep blood calcium levels from going too low by releasing calcium from bones, conserving calcium that would be excreted by the kidneys, and increasing calcium absorption from food. When the hormone overacts, the result is a rise in the blood calcium level.
What are symptoms of hyperparathyroidism?
The following are the most common symptoms of hyperparathyroidism. However, each individual may experience symptoms differently. Symptoms may include:
- Loss of appetite
- Increased thirst
- Frequent urination
- Lethargy and fatigue
- Muscle weakness
- Joint pain
- Kidney pain (due to the presence of kidney stones)
Other serious symptoms may include:
- Abdominal pain
- Memory loss
What causes primary hyperparathyroidism?
In some cases, no cause can be identified. Some known causes include benign (non-cancerous) tumors on the parathyroid glands, or enlargement of the glands. In the United States, about 100,000 people develop the disorder each year. Women outnumber men two to one, and risk increases with age. In women 60 years and older, two out of 1,000 will develop hyperparathyroidism each year.
Primary hyperparathyroidism is a disorder of one or more than one parathyroid glands. This problem originates in the parathyroid glands opposite to secondary or tertiary hyperparathyroidism, which cause parathyroids to be overactive, secondary to such a problem as kidney failure.
What are Secondary and Tertiary Hyperparathyroidism?
Secondary and tertiary hyperparathyroidism (HPT) usually results from hyperplasia. Secondary HPT occurs most commonly “secondary” to chronic renal failure (CRF). For this reason, secondary HPT is frequently referred to as renal HPT. Tertiary HPT occurs most commonly in the setting of renal transplant where patients with secondary HPT continue to have elevated PTH levels after receiving a renal allograft.
Diagnosis of Hyperparathyroidism
The disorder may not present symptoms or complications, and is sometimes discovered during a routine blood test as part of a physical examination. The blood test will check for elevated blood calcium and PTH levels. A diagnosis procedure for primary hyperparathyroidism may involve a dual X-ray absorptiometry, also called bone densitometry, to determine bone density and to reveal loss of bone tissue. Bone densitometry is also used to continually monitor the disorder.