Parathyroid glands go bad in one way...they make too much parathyroid hormone called Hyperparathyroidism. This page of Parathyroid.com discusses what happens when you have too much parathyroid hormone and develop hyperparathyroidism.
Parathyroid Disease is called "Hyperparathyroidism".

This is a Very Important Page. Read it more than once!

Hyperparathyroidism is a disease of the parathyroid glands...Too much parathyroid hormone is produced by an overactive parathyroid gland. This is called hyperparathyroidism.

In patients with hyperparathyroidism, one of the four parathyroid glands grows into a tumor and behaves inappropriately by constantly making excess parathyroid hormone regardless of the level of calcium. In other words, one of the parathyroid glands has lost its control mechanism and continues to make large amounts of parathyroid hormone without paying attention to how high the blood calcium is. Thus, even when the calcium level is high--when the parathyroids should not be making any hormone at all--one of the glands keeps making hormone. Why? Because one of the parathyroid glands developed a benign tumor and lost its inhibitions and controls. Remember as you read about hyperparathyroidism on these pages, it is a hormone problem secreted by a benign parathyroid tumor. It is not a cancer problem.  As you look at the picture below, you will see that one of the parathyroid glands has grown way too big--it is making too much hormone--thus causing hyperparathyroidism.

WHAT CAUSES EXCESS PARATHYROID HORMONE PRODUCTION?

The most common cause of excess hormone production (hyperparathyroidism) is the development of a benign tumor in one of the parathyroid glands. This enlargement of one parathyroid gland is called a parathyroid adenoma which accounts for about 94 percent of all patients with primary hyperparathyroidism (see chart below). This situation is illustrated in the picture on the right: one of the parathyroid glands has developed a tumor which is secreting all the hormone...the other three glands are small and responding appropriately to the high calcium by becoming dormant (the parathyroids are yellow and are situated behind the larger thyroid lobes shown in light pink). This out of control parathyroid gland is essentially never cancerous (less than one in 1000 is cancer---essentially all of them are benign tumors), however, it slowly causes damage to the body because it induces an abnormally high level of calcium in the blood which can slowly destroy a number of tissues. Parathyroid adenomas typically are much bigger than the normal pea-sized parathyroid (shown to scale) and will frequently be about the size of a walnut. Thus, the typical patient with hyperparathyroidism will have one parathyroid that has developed into a benign tumor (called an adenoma) which will range in size from an olive to a walnut. They will also have three normal parathyroid glands that will be about the size of a grain of rice. The picture to the left is a picture of a typical parathyroid adenoma (parathyroid tumor) that causes hyperparathyroidism. This is a VERY AVERAGE tumor size, shape, and color. Most people with hyperparathyroidism will have a tumor in their neck about this size. Remember, the normal parathyroid gland is about the size of a grain of rice... but one cell inside this normal parathyroid gland went out of control and started reproducing itself until a large tumor developed. This tumor will almost always continue to grow until it is removed. As it grows, it makes more hormone and will make you feel worse. This tumor is constantly making parathyroid hormone which is what takes the calcium out of your bones and makes the calcium in your blood too high.

Where did this parathyroid tumor come from? This is a great question, and the answer is quite simple... In most cases we don't know WHY parathyroid tumors form. But this is HOW a parathyroid tumor forms... The normal parathyroid gland is made up of about 80,000 very small parathyroid cells. Each one is exposed to lots of blood flow and they all measure the calcium in the blood. When the calcium is low, they make parathyroid hormone (called PTH). When the calcium is high, they stop making hormone. They normally turn on and off hundreds of times per day. All of these cells act independent of the other. Occasionally, one of these cells will go nuts and start reproducing itself... a million or more times. The crazy "mother" cell divides into two, then does it again, and again, and again; many times a day. Over a period of several years a tumor develops. This tumor mass (seen in the photos on this site) is made up of millions of cells all of which are sisters from one crazy "mother" cell. Each of these "daughter" cells inherited the craziness of the mom, and they don't pay attention to the calcium level in the blood. They are out of control, making PTH whenever they want, in as much concentration as they want. When you look at all the pictures of the parathyroid tumors on this web site, you will see a small (rice-size) yellow NORMAL gland with a dark-red tumor growing out of it. The tumor mass is composed of millions of crazy daughter cells from one mother cell that went nuts. If you have surgery at the Norman Parathyroid Clinic, you will get a photo of your tumor, and you can almost always see the normal gland from which the tumor arose.

This graph shows the parathyroid hormone levels in 7,500 patients operated on at the Norman Parathyroid Clinic for PRIMARY hyperparathyroidism. Normal blood levels of parathyroid hormone vary according to the lab that measures the hormone, but most labs have a normal level between 14 and 65. Each of the patients represented here had a parathyroid tumor removed from their neck. As you can see, most (but not all!) of them have parathyroid hormone levels that are above normal (above 65). 

Note that most patients with primary hyperparathyroidism have PTH levels ranging from 60 to 150. When patients have PTH levels above 200 it is because their tumor is very old (usually this means over 10-12 years old) and the tumor is composed of MANY cells. If your PTH level is over 200, then some doctor somewhere was asleep at the wheel. This should not be allowed to happen, and the amount of destruction to your body is generally worse. Also note that about 15% of patients that have a parathyroid tumor in their neck will have PTH levels that are in the "normal range". Let me say that again... about 15% of patients with hyperparathyroidism will have high calcium levels and NORMAL PTH levels. Realize that this is still hyperparathyroidism and they still have a parathyroid tumor in their neck... We say their PTH level is "inappropriately normal". In other words, it still shows that there is a tumor full of crazy, out of control cells because if they were normal parathyroid cells... they would sense the high calcium and they would shut down. If your calcium is high, and your PTH is not near zero (consistently 20 or below), then you almost certainly have a parathyroid tumor. GET IT OUT!

One final note... this graph shows PTH levels in patients with primary hyperparathyroidism. This graph is DIFFERENT from the graph at the bottom of our Diagnosis page which shows CALCIUM levels in patients with primary hyperparathyroidism. These graphs have the same shape and thus you could confuse them... but one looks at the PTH levels in the blood, and the other looks at the calcium level in the blood. These two graphs are central to the diagnosis of hyperparathyroidism.

Does Too Much Parathyroid Hormone and Calcium Cause Symptoms?

Hyperparathyroidism causes symptoms in almost everybody, but sometimes they are quite subtle. We have put all of this information on a different page: Click Here to Learn About Symptoms and DANGERS of Parathyroid Disease. It is VERY important for you to understand these few facts:

1. It is almost never normal to have a high calcium level in your blood.
2. Almost all patients with high calcium in the blood have a single bad parathyroid gland that is causing it. Your doctor may look for other causes... but the overwhelming odds are that you will end up with parathyroid disease. We have an entire page discussing the other even more rare causes of high blood calcium on this web site, but don't spend too much time there reading about things you don't have.
3. The one bad parathyroid gland is a tumor. It is a benign tumor (not cancer), but it is a tumor.
4. Most parathyroid tumors are between the size of an olive and a grape. Occasionally they can be as big as a golf ball... or bigger. The size doesn't matter... just how much hormone it produces and how much calcium it is taking out of your bones. We have photos of these tumors on another page.
5. An expert in parathyroid surgery can fix this problem in 20 minutes or less. So if your surgeon says that it will take 2 or 3 hours in the operating room... You may want to find an expert surgeon. As you will read on this site and every other web site (or book) ever printed on the topic, picking your surgeon is the most important step, since the outcomes (cure rates and complications) are directly related to surgeon experience. There is no other area of the body that has such variable anatomy.
6. Removing the bad parathyroid tumor will cure the hyperparathyroidism and will make the calcium level go back to normal WITHIN HOURS.
7. Removing the parathyroid tumor will change the patient's life. It will make you feel 10 years younger, and literally, change your life.  Read about symptoms on this page.

HOW MANY PEOPLE GET PARATHYROID DISEASE
(Hyperparathyroidism) ?

The incidence of parathyroid disease (hyperparathyroidism) is 1 in 2,500 people. Unfortunately, it is our opinion that about 60% of patients with hyperparathyroidism do not know they have it... they have high calcium levels but their doctors don't know what this means and so the high calcium is ignored. Often, when something bad happens (kidney stones, bad osteoporosis, severe depression), then the doctors pay attention to the high calcium. Hyperparathyroidism occurs in women more often than men (almost exactly 75% women, 25% men), and the average age is about 59 years old--but people of any age can get it. Young people do get parathyroid disease, but this is rare. We have an entire page dedicated to this topic--Click Here to read about Who Gets It?

HOW MANY OF MY PARATHYROIDS ARE BAD ???

A recently conducted scientific study of 6331 patients with primary hyperparathyroidism examined their final diagnosis to determine how many glands typically go bad in this disease. This study includes data collected on a portion of patients with this disease for 10 consecutive years (1987 - 1997). The complete data and statistical analysis was published March, 1998 in the Journal of the American College of Surgeons. The lead author was Dr. James Norman. The results are as follows:

Importantly... nearly all patients with hyperparathyroidism have 1 parathyroid tumor and three normal parathyroid glands. Many of those patients with 4 bad parathyroid glands (remember, only about 3-4% will have 4 bad parathyroids) have 4 bad glands because they are 1) on the drug Lithium for many years, or 2) have a parent and/or brothers/sisters with this disease (called "familial hyperparathyroidism"). Thus, if you don't have a parent with this disease and you have not been on the drug Lithium for 20 or more years, then you have a 94% chance that you have just one bad parathyroid gland.  Bottom line, if your doctor thinks treating hyperparathyroidism complex or complicated and tells you that you could have 4 bad glands then you may want to take this page to them. Hyperparathyroidism can be cured quite easily if you chose a surgeon that does this operation on a weekly basis (discussed on other pages of our web site). ALMOST EVERYBODY has just one bad parathyroid gland and it can almost always be fixed in 20 minutes or less. If your doctor or surgeon tells you that surgery is dangerous and complicated... then you may want to find a surgeon that thinks it's safe and simple! It is also very important to know that some expert parathyroid surgeons can perform parathyroid surgery in under 20 minutes even if you have 4 bad glands. DO NOT let the concept of having one bad gland versus 4 bad glands confuse you or influence your treatment. Nearly all patients with hyperparathyroidism will benefit from having surgery... the only choice you really need to make is to choose your surgeon. Then let the surgeon worry about 1 bad gland, 2 bad glands, or 4 bad glands.  As an example, the only difference in an operation for one bad gland and 4 bad glands when we are performing the operation is that those who have one bad gland have an operation that takes about 16 minutes on average, and operations for 4 bad glands takes about 19 minutes on average. Everything else is exactly the same... same anesthesia, same incision, same 1.5 hours in the recovery room... everything is the same. Why are we spending so much time talking about this?? Because this is a very frequent worry that people have. They worry that they are one of the 3-4 percent of patients that have more than one bad gland... If you pick your surgeon wisely, you will not have to worry about this!

Click here to read more about parathyroid anatomy and where the four parathyroid glands are located. Understand why it can be very hard to find the four parathyroid glands, and why surgeons who do hundreds of these operations per year have a much higher cure rate.

How the One Bad Parathyroid (the Adenoma)
Affects the Other Three.

To teach how the parathyroid glands respond normally to calcium levels and how the parathyroid glands are supposed to work, we will use your home's heating system in the winter as an example.

We all have a heater in our homes that is controlled by a thermostat. When we set the thermostat on 70 degrees, it is this temperature that the thermostat will constantly monitor and turn on the heater when the temperature drops. If the temperature drops to about 68 degrees, the thermostat detects it and turns on the heater. The heater warms the room until the thermostat recognizes the increase in temperature, and when it reaches 72 degrees the thermostat turns OFF the heater. In reality, the heater in your home will turn on and off about 50 times per day. The temperature in the room will vary some, from a little above 70 degrees to a little below, but we don't notice it when the thermostat is working normally.

All of our parathyroid glands have a built in "thermostat" (all endocrine glands do!). The thermostat in the parathyroid glands is very sensitive to calcium levels in the blood. The normal 'setting' for the thermostat in the parathyroid glands is for a calcium level between 8.5 and 10.2.  Calcium is not just responsible for our bone strength, but it is the source of electrical energy in our nervous system and muscles, thus humans want this element controlled very, very well. Calcium is the ONLY element in the body that has its own control system!

Normal parathyroid glands constantly monitor the calcium in the blood. When the calcium levels drop, the parathyroid glands turn on... and make parathyroid hormone (PTH). The PTH acts directly on the bones within minutes and takes some calcium out of the bones (we use the bones as a storage system for calcium). Now the level of calcium in the blood will increase a little--and the parathyroid glands recognize this and turn themselves off. Just like the thermostat that turned on when the temperature got low, the normal parathyroid glands turned on when the calcium got low.  And, just like the thermostat that turned off when the temperature in the room got warm, the normal parathyroid glands turn off and stop making PTH when the calcium rose a little bit. This is why your calcium will vary every time your doctor measures it... it's always a little different, but it is ALWAYS supposed to be in the normal range.

What happens in patients with Hyperparathyroidism?  Well that is now a simple answer.  One of the parathyroid glands developed a tumor. That tumor (an overgrowth of cells) will be about the size of an olive (typically) and it will do what it likes to do...MAKE HORMONE! So, you have this one big, bad parathyroid gland that is making hormone 24 hours per day... its thermostat is broken!  It does NOT respond to the high calcium levels and turn off...instead it is stuck in the "on position", and constantly makes parathyroid hormone (PTH).  Well, this PTH keeps working on your bones, taking calcium out of the bones and putting it in your blood. The bones become thin (osteoporosis), and the calcium in the blood is elevated out of the normal range. We get nervous system symptoms due to the brain not liking the high calcium levels (depression, tiredness, mean-ness, lack of energy, problems sleeping, etc). We can also get kidney stones and other problems due to all the extra calcium floating around.

What happens to the NORMAL parathyroids when you have one bad parathyroid gland? Well that answer is now clear also.  In the overwhelming majority of people with hyperparathyroidism, they will have one bad gland and 3 normal glands. The one bad gland is big and producing PTH all day long...making the calcium go high.  Well, the three normal glands will still have a normal thermostat. They will recognize the high calcium and shut down their hormone making apparatus. Thus they become dormant and go to sleep.  Since most people with parathyroid disease don't get diagnosed until they have had it for years--the normal parathyroid glands will have been dormant for years by the time the surgeon operates to take out the bad one. This is why experienced surgeons will provide their patients with calcium pills to take for the first few weeks after parathyroid surgery. It will take a week or two for the normal parathyroid glands to wake up and begin to regulate the calcium normally (to get their thermostats working properly). Without taking lots of calcium during that time, your calcium can drop too low and you will get sick (have problems with your nervous system and brain, like feel bad, feel 'foggy' and confused, fell anxious and 'doomed', feel out of control; get tingling in your hands and fingers and around your mouth, get cramps in your hands and feet).  These are all symptoms of LOW calcium, and they can happen to patients after a SUCCESSFUL parathyroid operation. The symptoms are TEMPORARY, and will go away after the nervous system gets used to the new 'normal' calcium levels. It may take 2 - 5 days, but these symptoms will always go away, and they are always treated the same way--take more calcium!!!  If you get these symptoms after a parathyroid surgery--it means the surgery was successful, but your body doesn't like the new calcium levels yet and wants more calcium. You MUST give it more calcium if you have these symptoms. (Please understand, 94% of people will NOT have these symptoms as long as they take their calcium pills after the surgery)... and the ones that do have symptoms of low calcium simply have to take MORE calcium. (Note, these statistics come from our recent publication where we studied this in 3000 consecutive patients who went home within 1.5 hours of their operation. Of course, this is why all our patients get our home phone and cell phone numbers).

This page was last updated 04/19/2008. Parathyroid disease, hyperparathyroidism, primary hyperparathyroidism, parathyroid tumor, parathyroid surgery, parathyroid gland, parathyroidism.

Click here to read more about parathyroid surgery (the old fashioned way). DO NOT DO THIS!
Click here to read about the NEW way of performing parathyroid surgery (mini-parathyroid surgery). Fix the problem in 20 minutes or less... and go home in an hour or two!
Click here to read a patient's description of his problem and how he felt after he was cured. GOOD!
Click here to see more pictures of parathyroid tumors removed from people's necks.