Why is Parathyroid Hormone (PTH) high? Causes, symptoms, and what to do

Parathyroid Hormone (PTH) is a hormone produced by the parathyroid glands, which are small glands located behind the thyroid in your neck. It plays a crucial role in regulating the levels of calcium, phosphorus, and vitamin D in your blood and bones. If your PTH levels are high, it could indicate an imbalance in these minerals, which is important to understand and address.

What does Parathyroid Hormone (PTH) do?

PTH is responsible for maintaining the right balance of calcium in your bloodstream. It does this by:

• Stimulating the release of calcium from bones: PTH increases the activity of osteoclasts, which are cells that break down bone tissue, releasing calcium into the blood.
• Increasing calcium absorption in the intestines: It promotes the activation of vitamin D, which helps your intestines absorb more calcium from the food you eat.
• Reducing calcium loss in urine: PTH signals your kidneys to retain calcium, preventing it from being excreted in urine.

These actions ensure that your body has enough calcium to perform essential functions, like nerve transmission and muscle contraction.

Causes of high Parathyroid Hormone (PTH) levels

High PTH levels, also known as hyperparathyroidism, can be caused by several conditions:

• Primary hyperparathyroidism: This is the most common cause and occurs when one or more of the parathyroid glands become overactive, often due to a benign tumor called an adenoma.
• Secondary hyperparathyroidism: This occurs as a result of another condition, such as chronic kidney disease or vitamin D deficiency, that causes low calcium levels, prompting the parathyroid glands to produce more PTH.
• Tertiary hyperparathyroidism: This is a rare condition that can develop after long-term secondary hyperparathyroidism, where the glands become permanently overactive.

Symptoms of high Parathyroid Hormone (PTH) levels

High PTH levels can lead to a variety of symptoms due to the elevated calcium levels in your blood, a condition known as hypercalcemia. Symptoms may include:

• Fatigue and weakness
• Bone pain and fragility
• Kidney stones
• Increased thirst and urination
• Abdominal pain
• Mood changes or depression

However, some people with high PTH levels may not experience noticeable symptoms, especially in the early stages.

How to interpret high Parathyroid Hormone (PTH) test results

If your blood test indicates high PTH levels, your doctor will likely consider several factors, including:

• Calcium levels: High calcium levels along with high PTH can suggest primary hyperparathyroidism.
• Vitamin D levels: Low vitamin D levels can lead to secondary hyperparathyroidism.
• Kidney function tests: Poor kidney function can also result in secondary hyperparathyroidism.

Your doctor may recommend additional tests or imaging studies to determine the underlying cause of high PTH levels.

Managing high Parathyroid Hormone (PTH) levels

Treatment for high PTH levels depends on the underlying cause. Options may include:

• Surgery: For primary hyperparathyroidism, removing the overactive gland(s) can often resolve the condition.
• Medications: In cases of secondary hyperparathyroidism, medications to manage calcium and phosphorus levels, or vitamin D supplements, may be prescribed.
• Lifestyle changes: Maintaining a balanced diet with adequate calcium and vitamin D, and staying hydrated can help manage symptoms.

Frequently asked questions

What is a normal PTH level?
Normal PTH levels can vary depending on the lab, but they are generally within a range that supports normal calcium metabolism. Your doctor can interpret your specific results in context.

Can high PTH levels affect bone health?
Yes, high PTH levels can lead to increased bone breakdown, which may weaken bones and increase the risk of fractures.

Is high PTH always a cause for concern?
Not necessarily. Sometimes elevated PTH levels may not require immediate treatment, especially if they are mild and not causing symptoms. Your doctor will guide you based on your overall health and test results.

When to see a doctor

If you have been diagnosed with high PTH levels or are experiencing symptoms like persistent fatigue, bone pain, or frequent kidney stones, it is important to consult with your healthcare provider. They can help determine the cause and appropriate treatment plan. Regular monitoring and follow-up tests may also be necessary to manage your condition effectively.

Remember, this information is for educational purposes only and should not replace professional medical advice. Always discuss your lab results and health concerns with your doctor.