1/22/2009

Hyperparathyroidism: Symptoms & Treatment

Hyperparathyroidism is a disorder of the parathyroid glands in which one or more enlarged, overactive parathyroid glands secretes too much parathyroid hormone (PTH). The condition can be primary, when the problem is in these glands, and secondary – when a problem such as kidney failure causes ...
Hyperparathyroidism is a disorder of the parathyroid glands in which one or more enlarged, overactive parathyroid glands secretes too much parathyroid hormone (PTH). The condition can be primary, when the problem is in these glands, and secondary %26ndash; when a problem such as kidney failure causes the parathyroid glands to be overactive. Parathyroid hormone has many important functions in our body, but the primary is regulation of blood calcium! When the level of calcium in the blood falls too low, the parathyroid glands secrete just enough PTH to restore the blood calcium level. Treatment depends on several factors, including which type of hyperparathyroidism is being treated.


Frequency of the condition



Hyperparathyroidism is a common and often asymptomatic endocrine disorder with an estimated prevalence of 100 cases per 100,000 population. Of the endocrine disorders, only diabetes mellitus and hyperthyroidism occur more frequently than hyperparathyroidism. Twice as many women as men develop primary hyperparathyroidism, and risk increases with age. Two out of every 1,000 women age 60 and older will develop the disease. Infants and adults with vitamin D deficiency are at greater risk of developing secondary hyperparathyroidism.


Anatomy of parathyroid glands



Everyone should know that there are four of them and that they are in fact pea-sized glands located on the thyroid gland in the neck. Some researches have confirmed that, occasionally, a person could be born with one or more of the parathyroid glands embedded in the thyroid, in the thymus, or located elsewhere around this area. Many people confuse these parathyroid glands with thyroid gland and although their names are similar- they are entirely different glands, each producing different hormones with specific functions. The fact is that the parathyroid glands secrete parathyroid hormone- PTH, a substance that helps maintain the correct balance of calcium and phosphorous in the body.





PTH regulates the level of calcium in the blood, release of calcium from bone, absorption of calcium in the intestine, and excretion of calcium in the urine.


Why is calcium so important?



Although not too many people know about this- calcium is in fact essential for good health because it plays an important role in bone and tooth development and in maintaining bone strength. Not only that %26ndash; it is proven that this mineral is also important in nerve transmission and muscle contraction. It is a main part of every cell with many roles in each. Calcium is the most abundant mineral in our body which primary role is in keeping teeth and bones healthy. But calcium also helps your blood clot, aids in the transmission of signals in nerve cells and is involved in muscle contraction. Important thing is that phosphorus, another mineral, works in conjunction with calcium in these areas. Vitamin D also is also involved in regulating the amount of calcium in blood. Several researches done in the past have proven that PTH raises calcium levels by releasing calcium from your bones and increasing the amount of calcium absorbed from your small intestine. When blood calcium levels are too high, the parathyroid glands produce less PTH.


Mechanism of the condition



When we talk about primary hyperparathyroidism, we should know that this is the case where the parathyroid glands secrete too much hormone. Logically- calcium balance is disrupted and blood calcium rises. This condition is called hypercalcemia. Unfortunately- in 85 percent of people with hyperparathyroidism, a benign tumor called an adenoma has formed on one of the parathyroid glands, causing it to become overactive. In most other cases, the excess hormone comes from two or more enlarged parathyroid glands, a condition called hyperplasia. What happens when parathyroid glands release of too much calcium into the bloodstream? The bones may lose calcium, and too much calcium may be absorbed from food. The levels of calcium may increase in the urine, causing kidney stones.


Signs and symptoms of hyperparathyroidism



Big diagnostic problem is that a vast majority of people with hyperparathyroidism have no signs or symptoms. And even when they do- symptoms are non-specific such as a feeling of weakness or fatigue, or vague aches and pains. Most common symptoms are:




  • Thinning bones, leading to an increased risk of fractures


  • Increased thirst and urination due to increased excretion of calcium in the urine


  • Nausea, vomiting or loss of appetite


  • Confusion or poor memory


  • Kidney stones


  • Heartburn or abdominal pain from peptic ulcer disease or pancreatitis


  • Muscle weakness or fatigue




Possible causes of hyperthyroidism



Experts are saying that hyperparathyroidism can occur as one of two types: primary hyperparathyroidism or secondary hyperparathyroidism.




  • Primary hyperparathyroidism




Most often, this type is caused by a benign growth (adenoma) on one of the parathyroid glands. This must not be confused with carcinoma! In rare cases, hyperparathyroidism may be caused by cancer of one of the parathyroid glands which is the worst possible scenario!




  • Secondary hyperparathyroidism




This type occurs when some other medical condition causes the parathyroid glands to produce too much PTH in response to chronically low levels of circulating calcium. Possible causes are:


%26middot; Kidney failure


%26middot; malabsorption problems and rickets


%26middot; severe vitamin D deficiency




Risk factors for developing hyperparathyroidism



Several factors have caused vitamin D deficiency among some infants and children. Main among these are:




  • Breast-feeding




Most people don%26rsquo;t know that the breast mild doesn't contain vitamin D and vitamin D supplement should be used!




  • Sunscreen use




Children who consistently use sunscreen may not receive enough sunlight to manufacture vitamin D in their skin.


Diagnosis of hyperparathyroidism



Patient should receive a diagnosis of hyperparathyroidism only if blood tests show high levels of both calcium and parathyroid hormone. Once hyperparathyroidism is diagnosed, doctor should recommend tests to check for complications of the disorder. These may include:




  • Bone mineral density test (bone densitometry)




Not too many people have heard about this noninvasive test, which requires virtually no preparation but can quickly assess risk of osteoporosis, a condition that causes weak, brittle bones that fracture easily. Good thing is that the procedure is quick, simple, and gives accurate results. Other tests that can accurately measure bone density include ultrasound and quantitative computerized tomography (CT) scanning.




  • Urine tests




Every patient should know that a simple 24-hour collection of urine can provide many information on patient%26rsquo;s kidney function and the amount of calcium excreted in urine.




  • Imaging tests




To check for kidney stones, your doctor may recommend an abdominal X-ray or ultrasound, a noninvasive diagnostic technique that combines high-frequency radio waves and computer processing to view internal organs %26mdash; in this case, your kidneys %26mdash; in detail.


Sometimes you and your doctor may choose not to treat hyperparathyroidism right away, especially if your blood calcium is only mildly elevated. If so, your doctor will likely want to check your calcium levels and kidney function every six months and may also recommend an annual abdominal X-ray and a bone density test every one to two years. If the disease doesn't become worse over time, you may not need to have these tests as often.




Treatment



Primary hyperparathyroidism
It is important to know that, if the patient doesn%26rsquo;t have symptoms and kidneys and bones are healthy, sometimes it is best to wait! If patient has complications, or moderate to severe symptoms, or calcium level is elevated even though he or she doesn't have symptoms, doctor should recommend one of the following:






  • Surgery




Until few years ago, surgery to remove one or more parathyroid glands was the only option and still is the gold standard treatment. Every patient should know that the entire operation can usually be performed through a 1-inch incision in neck and it takes less than an hour. The operation is highly effective!




  • Hormone replacement therapy




These last couple of years %26ndash; hormone replacement therapy became very popular! For women who have gone through menopause and have signs of osteoporosis -hormone replacement therapy (HRT) may be an alternative to surgery.




  • Medications




It is important to know that the drug Cinacalcet has been approved to treat secondary hyperparathyroidism in people with kidney disease and parathyroid cancer.




Secondary hyperparathyroidism
It is important to know that, when we talk about cases of secondary hyperparathyroidism, the first goal is to treat the underlying problem-in most cases- chronic kidney failure. Experts have traditionally used vitamin D replacement therapies to reduce the production of PTH. Only bad thing about this form of therapy is that, although effective, this can lead to excessively high levels of both calcium and phosphorus in people undergoing dialysis.