What is hypoparathyroidism?

Hypoparathyroidism is a rare disorder in which the parathyroid glands do not produce enough parathyroid hormone (PTH). The parathyroid glands are tiny glands located near and behind the thyroid gland in the neck.

Parathyroid hormone regulates the levels of calcium and phosphorus in the bloodstream, which is important for bone health and muscle function. When the parathyroid glands do not produce enough parathyroid hormone, the levels of calcium in the blood can drop and the levels of phosphorus can rise to unhealthy levels. Low calcium levels in the blood can lead to tetany, an increased excitability of the nerves that causes muscle spasms and cramps.

Causes of hypoparathyroidism

The most common cause of hypoparathyroidism is accidental damage to or removal of a parathyroid gland during thyroid or neck surgery.

Other causes of hypoparathyroidism in children include:

• Autoimmune conditions that cause the body to attack healthy tissue, damaging the parathyroid glands
• Being born without parathyroid glands or with poorly functioning parathyroid glands, sometimes as a result of an inherited or spontaneous genetic mutation, such as 22q11.2 deletion

In some cases, the parathyroid glands have a sudden decline in function due to unknown reasons (idiopathic).

Signs and symptoms of hypoparathyroidism

Symptoms of hypoparathyroidism vary widely, and each person may experience symptoms differently. Symptoms may include:

• Numbness or tingling around the mouth or in the hands or feet
• Uncontrollable, painful spasms of the face, hands, arms and feet
• Muscle spasms that cause difficulty breathing or speaking
• Muscle cramps
• Seizures
• Low blood pressure
• Emotional instability, anxiety or depression
• Dental problems, such as late-developing teeth or weakened tooth enamel
• Coarse, brittle hair
• Brittle, easily broken fingernails and toenails

In severe, untreated cases, hypoparathyroidism can affect a child’s bone development, resulting in short stature.

The symptoms of hypoparathyroidism may resemble other problems or medical conditions. Always consult your child's doctor for a diagnosis.

How is hypoparathyroidism diagnosed?

In addition to a complete medical history and physical examination, diagnostic tests for hypoparathyroidism may include:

• Blood tests to measure levels of parathyroid hormone (PTH), calcium, phosphorus and magnesium
• Urine tests to measure levels of excreted calcium
• EKG to check for abnormal heart rhythm

Treatment for hypoparathyroidism

Treatment for hypoparathyroidism focuses on reducing symptoms by restoring and maintaining healthy levels of calcium and phosphorus in the blood. The specific treatments will be determined by your child's doctor in consultation with you.

Treatment may include:

• Calcium and vitamin D supplements
• Calcitriol, the active form of vitamin D available only as a prescription
• Diuretics to reduce the amount of calcium excreted in urine
• Medications, such as sevelamer, to bind phosphorus in the diet
• Injections of calcium for immediate relief of severe symptoms
• PTH hormone replacement therapy, when calcium and vitamin D supplements don’t work to restore mineral balance and reduce symptoms

Calcium and vitamin D supplements, when effective in reducing symptoms, are taken daily, as a lifelong treatment.

Diet may also be a part of treatment, with nutritional counseling to help patients and their families choose foods that are high in calcium and low in phosphorus.

Periodic blood tests are done to monitor calcium and phosphorus levels and adjust treatment as needed.

Follow-up care

Ongoing care, coordinated by a primary care physician or specialist who is knowledgeable about hypoparathyroidism is essential to the long-term health and well-being of patients. Because the disorder can affect different body functions, coordinated care by a team of appropriate specialists is needed.

Treatment of hypoparathyroidism at Children’s Hospital of Philadelphia (CHOP) is managed in the Division of Endocrinology and Diabetes. In some cases, patients may be referred to a specialists in the Center for Bone Health, which provides comprehensive, coordinated care in collaboration with other specialty departments.

Depending on the patient’s diagnosis and condition, coordinated care might include specialists in:

• Orthopedics
• Endocrinology
• Pain management
• Dental care
• Physical and occupational therapy
• Nutrition
• Genetics