Hyperparathyroidism

Hyperparathyroidism is when the parathyroid glands produce too much parathyroid hormone.

The parathyroid glands are four tiny glands in the neck, near the thyroid, that produce parathyroid hormone (PTH). Parathyroid hormone regulates calcium and phosphorus levels in the blood, which helps with nerve, muscle, and bone health.

With hyperparathyroidism, the parathyroid produces too much PTH. Excess parathyroid hormone can lead to several health problems. There are two main types of hyperparathyroidism: primary and secondary hyperparathyroidism.

Learn more about hyperparathyroidism, including its types, causes, symptoms, diagnosis, treatment, and potential risks and complications.

What is hyperparathyroidism?

Hyperparathyroidism occurs when the parathyroid glands, located behind the thyroid gland in the neck, produce too much parathyroid hormone. Parathyroid hormone (also called PTH) helps regulate calcium levels in the blood by increasing calcium release from bones, absorption from the intestine, and reabsorption from kidneys. Excess PTH can lead to hypercalcemia (high calcium levels) and associated symptoms.

What are the types of hyperparathyroidism?

There are two main types of hyperparathyroidism. Both types involve the parathyroid producing more PTH than normal. The type depends on whether the excess PTH is due to a problem with the parathyroid or another health condition.

• Primary hyperparathyroidism: One or more or the parathyroid glands produces too much PTH.
• Secondary hyperparathyroidism: When another health condition causes you to have high phosphate levels or low levels of calcium or vitamin D, the parathyroid produces more PTH to regulate these levels. This is most common in people with kidney disease.

Causes of hyperparathyroidism

Primary hyperparathyroidism

Primary hyperparathyroidism is most commonly caused by:

• Parathyroid adenoma: A benign tumor in one of the parathyroid glands causing excessive PTH production.
• Multiple gland hyperplasia: Enlargement of two or more parathyroid glands resulting in overproduction of PTH.
• Parathyroid carcinoma: A rare, malignant tumor of the parathyroid glands.

Secondary hyperparathyroidism

Secondary hyperparathyroidism is often caused by conditions that induce low calcium levels, prompting increased PTH production:

• Chronic kidney disease: Impaired kidney function reduces calcium levels and phosphate regulation, stimulating parathyroid glands.
• Vitamin D deficiency: Low vitamin D levels hinder calcium absorption, leading to increased PTH production.

Tertiary hyperparathyroidism

Tertiary hyperparathyroidism occurs in patients with prolonged secondary hyperparathyroidism, where parathyroid glands become overactive and autonomous:

• Chronic kidney disease: Persistent stimulation leads to autonomous parathyroid gland function.

What are the symptoms of hyperparathyroidism?

Symptoms of hyperparathyroidism may be difficult to notice. Some symptoms can seem related to other health problems. Many people do not experience noticeable symptoms.

Signs and symptoms of hyperparathyroidism may include:

• Fatigue: Persistent tiredness and lack of energy.
• Muscle weakness: Generalized weakness, particularly in the proximal muscles.
• Bone pain: Pain or tenderness in bones due to bone resorption.
• Joint pain: Aching or discomfort in joints.
• Kidney stones: Formation of calcium-based stones in the kidneys.
• Frequent urination: Increased urine output due to high calcium levels.
• Thirst: Increased thirst, often associated with frequent urination.
• Digestive issues: Nausea, vomiting, constipation, and abdominal pain.
• Neuropsychiatric symptoms: Depression, anxiety, confusion, memory problems.
• Hypertension: Elevated blood pressure.

Long-term effects

Prolonged hyperparathyroidism can lead to serious health problems, including:

• Osteoporosis: Bone loss due to chronic high PTH levels.
• Pathological fractures: Increased risk of bone fractures.
• Renal impairment: Damage to kidneys due to high calcium levels.

Diagnosis of hyperparathyroidism

Because many people do not have noticeable symptoms, hyperparathyroidism is often diagnosed when a blood test for another reason shows high levels of calcium in the blood.

If your health care provider suspects that you may have hyperparathyroidism, they may perform a physical exam and ask about your medical history and symptoms.

Diagnostic tests that can help check for hyperparathyroidism include:

• Blood tests:
  • Serum calcium: Elevated calcium levels suggest hyperparathyroidism.
  • Parathyroid hormone (PTH): Elevated PTH confirms hyperparathyroidism.
  • Vitamin D levels: Checking for deficiency which may contribute to secondary hyperparathyroidism.
  • Serum phosphate: Often low in primary hyperparathyroidism and high in secondary.
• Urine tests:
  • 24-hour urinary calcium: Measures calcium excretion in urine to assess calcium metabolism.
• Imaging studies:
  • Sestamibi scan: Using a radiotracer to visualize overactive parathyroid glands.
  • Neck ultrasound: Visualizing the parathyroid glands and identifying adenomas or hyperplasia.
  • Bone density scan (DEXA): Assessing bone health and detecting osteoporosis.

How is hyperparathyroidism treated?

Treatment for hyperparathyroidism depends on the type, cause, and severity of the problem. In some cases, a health care provider may recommend watchful waiting. In other cases, treatment might involve medication or surgery.

• Watchful waiting: Regular monitoring of calcium and PTH levels, bone density scans, and kidney function tests.
• Medications: Used to lower PTH production, prevent bone loss, or supplement vitamin D.
• Parathyroidectomy: Surgical removal of the overactive parathyroid gland(s) is the definitive treatment for primary hyperparathyroidism and tertiary hyperparathyroidism. Surgery can involve:
  • Focused parathyroidectomy: Removal of the single adenoma identified by preoperative imaging.
  • Bilateral neck exploration: Examination and removal of multiple hyperactive glands in cases of hyperplasia or uncertain localization.

Potential risks and complications

Complications of untreated hyperparathyroidism

• Osteoporosis: Increased risk of bone fractures due to ongoing bone resorption.
• Kidney stones: Persistent formation of kidney stones leading to renal impairment.
• Cardiovascular risks: Elevated calcium levels contributing to hypertension and cardiovascular disease.
• Renal impairment: Chronic high calcium levels causing kidney damage.

Long-term considerations

• Ongoing monitoring: Regular blood tests to monitor calcium, PTH, and kidney function, and bone density scans to assess bone health.
• Medication management: Continued use of medications to manage calcium and PTH levels.
• Monitoring for recurrence: Continuous follow-up to ensure early detection of any recurrence or complications.

Impact on quality of life

• Symptom relief: Effective treatment can alleviate symptoms, normalize calcium levels, and significantly improve overall well-being and quality of life.
• Informed decision-making: Accurate diagnosis aids in making informed decisions about treatment and preventive measures.
• Emotional support: Providing counseling and support to address anxiety, depression, and the psychological impact of living with hyperparathyroidism or undergoing treatment.

Hyperparathyroidism is a condition that can significantly impact multiple organ systems if left untreated. Early diagnosis and appropriate intervention with medical treatments or surgery are crucial for managing symptoms and preventing complications. Understanding the causes, symptoms, diagnostic methods, and treatment options is essential for effective management. If you or a loved one are experiencing symptoms or have risk factors for hyperparathyroidism, consulting with a health care provider, endocrinologist, or specialized surgeon will help determine the need for further evaluation and develop a suitable treatment plan tailored to your specific needs and circumstances.