What Is Hypoparathyroidism?

Let's look at the causes and symptoms to help you understand why this rare condition occurs.

Causes

Surgery

Most common cause of acquired hypoparathyroidism

Any of the following surgeries can result in parathyroid damage:

  • Surgery on or the total removal of the thyroid or parathyroid glands
  • Surgery on structures near the parathyroid glands
  • Surgery to remove cancer in the neck

Hypoparathyroidism caused by surgery may last for a short time or become permanent. Doctors monitor and manage low calcium levels after surgery until parathyroid function returns to normal. If it does not return to normal within 6 months, “chronic hypoparathyroidism” is a typical diagnosis.

Autoimmunity

Second most common form
in adults

Autoimmune hypoparathyroidism can occur alone or as part of an autoimmune polyglandular syndrome (APS), a condition involving multiple autoimmune disorders associated with the endocrine glands.

Heredity

When the parathyroid glands either aren't present or don't work properly at birth, this is called hereditary or familial hypoparathyroidism.

Radiation

Very rare cause

Radiation treatment for cancer of the head or neck (or radioactive iodine treatment for hyperthyroidism) can damage the parathyroid glands.

Unknown

Very rare cause

Some cases of hypoparathyroidism appear not to be brought on by any known cause. Doctors refer to such conditions as “idiopathic.”

Signs and Symptoms

The neurologic, cognitive, muscular, and cardiac systems can be affected in a person with hypoparathyroidism who has hypocalcemia (low blood calcium). Here are some of the signs and symptoms that can occur when these systems are affected.

Physical

  • Tingling or burning in lips, fingers, feet, and toes
  • Facial numbness or twitching
  • Muscle spasms, twitching, and cramping
  • Weakness
  • Headaches
  • Abnormal excitability of nerves and muscles causing leg or arm spasms (tetany)

Cognitive/Emotional

  • Personality changes
  • Depression
  • Memory problems
  • Irritability
  • Confusion and disorientation also referred to as "brain fog"

Complications

Complications can occur due to low blood calcium and/or too much calcium being deposited in other tissues. In some cases, people may experience severe, possibly life-threatening complications, including seizures, kidney stones or kidney disease, heart rhythm disturbances, and abnormal bone formation.

How It's Diagnosed

Beyond a medical history—including symptoms, past neck surgery, and family history of hypocalcemia—diagnosis requires:

Hypoparathyroidism diagnosis can happen through physical exams.

for neuromuscular symptoms, including Chvostek's sign (facial twitching in response to stimulation) and Trousseau's sign (muscle spasms in the hand and forearm)

Hypoparathyroidism diagnosis can happen through blood tests.

for total serum calcium, ionized calcium (calcium that is flowing freely in your blood), magnesium, phosphate, vitamin D, and parathyroid hormone

Hypoparathyroidism diagnosis can happen through a urine test.

for excessive excretion of calcium and to check kidney function

During this time, doctors may also:

  • Test your heart for rhythm abnormalities
  • Check your eyes for cataracts
  • Take images of your kidneys to look for calcium deposits
  • Perform a bone density scan
  • Perform more blood tests to rule out other causes of hypocalcemia

If tests show that you have low levels of calcium flowing freely in your blood, inappropriately low PTH, and high phosphorus, hypoparathyroidism could be the cause of your hypocalcemia.