The causes of hypoparathyroidism can be genetic conditions or conditions that develop after birth, but surgery accidents are the most common cause of hypoparathyroidism. The four parathyroid glands are located behind the thyroid gland, and the parathyroid glands may become damaged or accidentally removed during thyroid or parathyroid surgery or other surgeries that involve the neck or throat. The absence of or damage to the parathyroid glands result in insufficient parathyroid hormone (PTH) production, leading to the abnormally low blood calcium levels (hypocalcemia) that cause the symptoms of the disease.
Other causes of hypoparathyroidism include:
- Genetic abnormalities – Some individuals lack parathyroid glands at birth or don’t have functioning parathyroid glands when born. Others have genetic disorders like DiGeorge syndrome that prevent the parathyroid glands from functioning properly.
- Low blood magnesium levels – The parathyroid glands need magnesium to produce PTH, and insufficient magnesium levels can prevent the parathyroid glands from producing enough of the hormone.
- Autoimmune disease – This type of disease causes the immune system to produce antibodies that target the parathyroid glands. When the antibodies attack parathyroid gland tissue, it may stop the production of PTH.
- Radiation treatment – The radiation from cancer treatment can damage or destroy the parathyroid glands. The use of radioactive iodine for treating hyperthyroidism can also damage the parathyroid glands.
These hypoparathyroidism causes also result in insufficient PTH production and low blood calcium levels. Low PTH levels also cause elevated blood phosphorus levels (hyperphosphatemia).
U.S. News & World Report has ranked Tampa General Hospital as one of America's Best Hospitals for Diabetes & Endocrinology. When a patient shows signs of having hypoparathyroidism, the physicians at the TGH Thyroid Cancer & Parathyroid Institute can check if any of the causes of hypoparathyroidism are present, and, if so, also provide treatment for the condition.