Hyperparathyroidism: causes, symptoms, and treatment

Hyperparathyroidism is a condition of the parathyroid glands which causes excess calcium to be present in the blood. Dr Mark Vanderpump, expert consultant endocrinologist specialising in thyroid problems, discusses the condition in this Q & A session with Top Doctors. 

What is hyperparathoidism? 

The parathyroid glands are located in the neck in and around the thyroid gland. There are four of them, and they are pea-sized glands. They’re important glands that make and secrete the parathyroid hormone, which is an important regulator of our calcium levels in the blood. Mostly they act through the bones, the kidney, and the gut. They regulate the calcium levels, because there body needs to have a certain level of calcium that it is designed to have as an ideal, helping our body function.

Primary hyperparathyroidism is a biochemical state in which one or more of those glands starts increasing the parathyroid hormone secretion, sometimes through a genetic cause where the size of the gland is increased, or sometimes because it becomes a benign adenoma. As an outcome of that, calcium levels in the blood rise as the parathyroid hormone brings calcium into the blood from the gut, kidney, and the bone.

What are the symptoms of hyperparathyroidism?

The symptoms of primary hyperparathyroidism relate to the level of calcium in the blood, of course, not the level of the hormone. These symptoms are dictated by how long the calcium has been there and how severely elevated the calcium is.

Nowadays, many patients discover this elevated level of calcium as a coincidental finding when they have a blood test for something else, as it is a relatively mild disorder where often there are no symptoms or some non-specific tiredness, or a mood disorder is present.

Historically, primary hyperparathyroidism is associated with the development of kidney stones with loss of bone density and increased fracture risk, gut symptoms such as gastritis, and if present at severe levels, can make the patient have symptoms they might believe are similar to diabetes, with increased thirst and passing of urine.

Even in extreme cases when a patient becomes very dehydrated, they can have a kidney crisis and this often presents an acute medical emergency. However, the vast majority of people probably don’t display many symptoms that they can attribute to their raised calcium.

Who is at risk of hyperparathyroidism?

Primary hyperparathyroidism is thought of as being a disease associated with ageing so if one screens the elderly population, it becomes much more common. It is seen in the younger age group as well, often sporadically, which just means that it just happens for no reason in a proportion of people.

Particularly in the younger age group, there may be a genetic cause and primary hyperparathyroidism is linked to other rare endocrine genetic syndromes. Younger patients are often screened for other tumours: benign tumours such as in the adrenal gland and the pituitary. However, for the vast majority of people it will just be seen as an isolated problem where for some reason, there’s increase in growth of a single, or all of those four parathyroid glands with no obvious cause found or genetic studies available.

In those who have kidney stones or early osteoporosis, screening is important, because those would be two signs that you might have had unknown primary hyperparathyroidism for some years, along with people who have gut-related symptoms such as gastritis. 

Once the diagnosis is secure from blood tests, we do a urine test to confirm increased calcium excretion in the urine. Once you’re secure with your diagnosis, the main issue is whether the patient has symptoms or not and whether they need intervention.

What is the treatment for hyperparathyroidism?

One of the problems with hyperparathyroidism is that surgery is now really the only option for treatment, as the specialist has to find if it is just one, or four of the glands which is causing the problem. They must then remove that gland surgically. There are no medical treatments available.

Once the gland or glands causing the problem have been identified, patients can choose whether or not they want to go forward for an operation and often in many cases, I would advise patients to adopt a conservative approach. It does appear that many patients can live with a relatively mildly raised calcium for many years without suffering any long term harm and it’s a perfectly acceptable option to just watch and wait and see if their calcium rises or become symptomatic in the future.

The treatment options for hyperparathyroidism are actually quite clear: you either opt for surgery with various criteria or you adopt a 'wait and see' policy to see whether you justify surgery at some point in the future.