PTH, Intact without Calcium

What this laboratory test evaluates

DetailsThis test checks the levels of intact parathyroid hormone (PTH) in the blood, helping diagnose various conditions related to calcium levels in the body. It's particularly useful for understanding issues like too little calcium (hypocalcemia) or too much calcium (hypercalcemia) in the blood. Conditions such as hyperparathyroidism, hypoparathyroidism, hypercalcemia of malignancy, or mineral and bone disorder due to chronic kidney disease can be managed and diagnosed with this test.

Why might you need this test?Doctors might suggest this test if a patient exhibits symptoms or is at risk for calcium imbalance disorders. It helps in:

• Evaluating low calcium levels to check for inadequate PTH secretion (hypoparathyroidism).
• Diagnosing high calcium levels to identify over-secretion of PTH (hyperparathyroidism or ectopic PTH production).
• Monitoring mineral and bone disorder in chronic kidney disease patients from stage G3a onwards.
• Assessing parathyroid disorders after bariatric surgery due to chronic calcium and vitamin D deficiency.

Since PTH levels are interpreted with calcium levels, a simultaneous blood calcium test is usually needed.

How does it work?This test uses a special technique that involves antibodies targeting different parts of the PTH molecule, ensuring accurate detection of intact PTH molecules. It's reliable even in patients with renal failure, as it's not influenced by C-terminal fragments or most drugs and supplements, including biotin.

What type of sample is required?1.5 mL plasma collected in an EDTA (lavender-top) tube.

Test Resources https://education.questdiagnostics.com/faq/FAQ202

Additional test information

This test checks the levels of intact parathyroid hormone (PTH) in the blood, helping diagnose various conditions related to calcium levels in the body. It's particularly useful for understanding issues like too little calcium (hypocalcemia) or too much calcium (hypercalcemia) in the blood.

Collection and processing

• Sample type: Plasma
• Fasting: No
• Estimated laboratory processing: Results should be available in 2 – 5 business days after the sample is collected

How Sunridge uses laboratory information

Sunridge considers the medical question, symptoms, history, medications, prior results, and whether the finding could change care before recommending testing. A laboratory result is not interpreted in isolation and does not establish a diagnosis by itself.

Before requesting this test

Availability, collection requirements, eligibility, and processing estimates can change. Sunridge reviews each request and, when appropriate, creates the order through Fullscript. Follow the current instructions supplied with the approved order.