The parathyroid glands are located in the neck in and around the thyroid gland. There
are four of them. They’re pea-size glands. They’re important glands that make and secrete
the hormone 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 as there’s a certain level of calcium that we’re designed to
have as an ideal level that helps our body function.
So primary hyperparathyroidism is a biochemical state in which one or more of those glands
sometimes through a genetic cause where you have an increased size of the gland or it
becomes a benign adenoma, for whatever reason they start increasing the parathyroid hormone
secretion. So what you see as an outcome of that is that you have raised calcium levels
in the blood as the parathyroid hormone brings in calcium into the blood from the gut, kidney,
and the bone.
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 of my patients have found this
as a coincidental finding when they have a blood test for something else and is a relatively
mild disorder where often there are no symptoms or some non-specific tiredness or mood disorder.
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 for severe level can make patient have symptoms they might think 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 actually present as an acute medical emergency.
But the vast majority of people probably don’t have many symptoms that they can attribute
to their raised calcium.
Primary hyperparathyroidism is thought as
being a disease of 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 particularly in the younger age group, there
may be a genetic cause and primary hyperparathyroidism is linked to other rare endocrine genetic
syndromes. So often, younger patients are screened for other tumours: benign tumours such as in the
adrenal gland and the pituitary. But for the vast majority of people it will just be seen as an
isolated problem where for some reason, there’s increased growth of a single or all of those
four parathyroid glands with no obvious cause found or genetic studies available.
It’s important in terms of screening that people who have kidney stones or have early
osteoporosis because those would be two signs that you might have unknown primary hyperparathyroidism
for some years and people who have symptoms in their gut such as gastritis, again calcium
can cause that. So there are some groups that you might think about calcium much more than
others in terms of doing that blood test to make the diagnosis.
Once the diagnosis is secure and that’s from blood tests and also 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. It tends to be the younger patients with the
more severe blood tests and also those with evidence who what we call endo organ damage.
For example, if there’s clear evidence of damage to the kidneys and the bones, those
are the groups of people who are offered intervention. The problem is that surgery is now really
the only option because what you have to do is to find if one or four of the glands is
causing the problem and they remove that gland surgically. There’s no medical treatment
available. Once you make that decision, 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 because 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 option is actually a 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.