The parathyroid glands are small endocrine glands in the neck that play a crucial role in calcium homeostasis, which is essential for various bodily functions including bone health, muscle function, and nerve signaling.
Humans typically have four parathyroid glands, though the number can vary, located on the back of the thyroid gland in the neck.
Structure
1) Location and Number
Usually four glands (two on each side), positioned behind the thyroid gland, though this can vary.
2) Size and Shape
Each gland is small, about the size of a grain of rice (3-4 mm in length), and has a reddish-brown color.
Function of Parathyroid glands
The parathyroid glands regulate calcium and phosphate levels by secreting parathyroid hormone (PTH).
PTH increases calcium levels in the blood by:
Stimulating calcium release from bones.
Increasing calcium absorption in the intestines (via vitamin D activation).
Increasing calcium reabsorption in the kidneys.
PTH also reduces phosphate reabsorption in the kidneys, increasing phosphate excretion.
Disorders of the Parathyroid Glands
1) Hyperparathyroidism
Overproduction of PTH, causing high calcium levels (hypercalcemia).
Often caused by a benign tumor (adenoma).
Symptoms include osteoporosis, kidney stones, fatigue, and depression.
2) Hypoparathyroidism
Underproduction of PTH, leading to low calcium levels (hypocalcemia).
Causes include surgery, autoimmune disease, or genetic factors.
Symptoms include muscle cramps, tingling, and in severe cases, seizures.
3) Secondary Hyperparathyroidism
Occurs in response to low calcium levels, often due to chronic kidney disease or vitamin D deficiency.
Prolonged condition can lead to bone disease
Treatment of Parathyroid glands
Treatment for parathyroid disorders depends on the type, cause, and severity of the condition. It may include:
Surgery: Often recommended for primary hyperparathyroidism, to remove the overactive gland(s).
Medication: Drugs may be used to manage symptoms or the underlying cause, such as vitamin D analogs, calcium supplements, or drugs that mimic calcium to inhibit PTH secretion in cases of hypoparathyroidism.
Monitoring: In cases where immediate treatment isn't necessary, regular monitoring of blood calcium levels and bone density may be advised.
Correctly diagnosing and managing parathyroid disorders is crucial for maintaining calcium balance and preventing complications associated with abnormal calcium levels.