Parathyroid hormone is a hormone that is produced by four glandolines located behind the thyroid, in the neck. It is an important hormone because it has the task of maintaining constant levels of circulating calcium. But why is calcium so important to our body? And when is it necessary to evaluate the level of parathyroid hormone in the blood? We talk about this topic with Dr. Andrea Lania, Head of Endocrinology at Humanitas.


Why is calcium important to our body?

“In addition to helping maintain healthy bones, calcium is important for a variety of biological functions such as nerve impulse transmission, muscle contraction, hormonal secretion, and some chemical and enzymatic reactions.

So it’s important that the calcium levels in our body are constantly maintained in a very narrow range as a rule.


When and why is the exam used to evaluate the parathyroid hormones levels?

“PTH determination alone is in no way sufficient to make a diagnosis of disease. In any clinical condition the patient is in, it is essential to associate this test with other tests, and in particular with the determination of circulating levels of calcium, phosphorus and vitamin D.

This series of tests is useful in all those conditions in which there are signs or symptoms suggestive of an altered calcium metabolism, for example in post-menopausal women with a picture of osteopenia or osteoporosis, or following the incidental detection of altered calcium levels.


What does the examination consist of?

“It is a simple blood collection, which helps to evaluate the levels of parathyroid hormone, calcemia, phosphoremia and vitamin D levels”.


What diseases, if any, is this examination associated with?

“The examination is generally performed in the presence of important diseases such as primitive hyperparathyroidism, a condition in which high levels of parathyroid hormone correspond to high levels of circulating calcium. It is also performed in the case of secondary hyperparathyroidism, a condition in which, in the presence of an elevated parathyroid, there are normal levels of calcium in the blood: this is a situation related to either a deficiency of vitamin D or chronic renal failure.

This parameter can also be useful in cases of hypocalcaemia, i.e. when a parathyroid malfunction is suspected, and therefore circulating parathyroid levels are reduced, especially in patients undergoing surgery at thyroid level”.


What happens if the test has been carried out in the last year or you are afraid that you have carried out the wrong test?

“First of all, it is important to reiterate that any test errors (overestimates) do not prejudice the patient’s health and that the test itself is never decisive for diagnosis and therapy, since it must be interpreted in the light of the patient’s clinical situation and associated with other clinical and laboratory parameters.

That said, to correctly interpret any type of clinical data, not only this test, it is important to consult your doctor or specialist (endocrinologist, rheumatologist, orthopedist or nephrologist). It is therefore a good idea to assess with your doctor whether or not you should repeat the examination”.


For more information, a dedicated number can be contacted: 02 8224 6203.