PTH may be requested when a blood calcium or phosphate result is abnormal. PTH may be requested when you have hypercalcaemia, which may cause symptoms such as tiredness, sickness, stomach pain, and thirst. PTH may also be requested when you have hypocalcaemia, which may cause symptoms such as muscle cramps and tingling fingers. Your doctor may request a PTH, along with calcium (and other tests) as a way of monitoring changes when you have had treatment for diseases or conditions that affect calcium regulation, such as the removal of a parathyroid tumour, or when you have chronic conditions such as kidney disease.When a person has hyperparathyroidism, the usual treatment is surgery to remove the enlarged gland or glands. Usually in primary hyperparathyroidism, only one abnormal parathyroid gland is present, but in some cases two or more of the glands are abnormal. In secondary hyperparathyroidism, usually all four of the parathyroid glands are affected. During surgery, it is important for the surgeon to make sure that all of the abnormal glands have been removed. If all are abnormal, this usually means removing three glands completely and part of the fourth, leaving behind just enough parathyroid tissue to prevent hypoparathyroidism. One way to be sure that all of the abnormal tissue has been removed is to measure PTH before and after an apparently abnormal gland has been removed. If all the abnormal tissue is gone, PTH levels will fall by over 50% within 10 minutes. To be useful, this requires that the laboratory be able to provide the results quickly (this is often called rapid or intra-operative PTH measurement). This is not available in all UK laboratories.
