Monday, January 30, 2012

"Is it depression or low thyroid?



In the last 25 years a great many good research studies have shown that up to 40% of what psychiatrists diagnose as depression, is actually thyroid imbalance. Many depressions, as well as instances of bipolar, that are refractory to standard psychiatric medicines are actually much better and more successfully treated with thyroid hormone. Dr. Shames further explained that, "Treatment with thyroid hormone is much less expensive and carries much less in the way of risks and side effects than the more standard treatment with Prozac or Zoloft, especially when mental sluggishness of low thyroid is mis-diagnosed as clinical depression."

Better ways of making a more accurate distinction between thyroid problems and depression now exist. Improved diagnostic technology is currently available via quality home test kits ordered by doctors or patients themselves through the internet. (www.CanaryClub.org) Dr. Shames applauds this innovation, since regular thyroid blood tests are so distressingly unreliable. According to this thyroid doctor, "The medical climate is ripe for change."

Richard Shames, MD is a practicing physician, teacher and author. He graduated Harvard and University of Pennsylvania, did research at the National Institutes of Health with Nobel Prize winner Marshall Nirenberg, and has been in private practice for twenty five years. In addition to his medical office work, he has been a member of the Clinical Faculty of the University of California Medical Center in San Francisco, a founding member of the American Holistic Medical Association, a participant in the Carl Menninger Foundation, and a member of Who's Who in California as well as nationally. He has served as Adjunct Faculty at Florida Atlantic University.

Dr. Shames has published a number of health-related books. In addition, he is a popular speaker and local media personality, and has created his own audio and video tape series. The author is well known for his prominence and pioneering work in the holistic field. His newest book is Thyroid Mind Power.

For more information please contact Julie Dietz at Preventive Medical Center of Marin l ocated at 25 Mitchell Blvd # 8 San Rafael, CA 94903. She can be reached at 415-472-2343 extension 7. For further information about Dr. Shames, visit www.thyroidpower.com

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For the original version on PRWeb visit: www.prweb.com/releases/prweb2011/11/prweb8965393.htm


Friday, January 27, 2012

What is Thyroid-Related Fatigue?

Energy is the backbone of life. All systems in your body need energy to function properly. How you produce and distribute energy is complex; thyroid hormone function has a major impact on all of your energy systems. However, not all fatigue or tiredness is due to thyroid malfunction. 


How do you tell the difference?


Thyroid hormone governs the basal metabolic rate, which is like the idling speed of a car engine. Even when you are sitting in a chair or sleeping your 100 trillion cells keep making energy. This type of energy production is the foundation for all other energy and hormonal systems. If it is not up to par, no other system in your body works as well as it should.


When you step on the gas pedal during the day, this is not thyroid hormone that goes into action. Increased activity of any kind is controlled by adrenaline, muscle activity, increased calorie burning, and an increased speed at which your cells make energy. If you have a sluggish thyroid you may still be able to make yourself have the energy to do things based on adrenaline-driven necessity. You may also notice that you have too much reliance on stimulants such as caffeine, sugar, or cigarettes.


A demanding day may deplete muscles of fuel and induce enough wear and tear so that natural tiredness follows. Such fatigue is normal and why we need to sleep. Even pushing it day after day and cutting sleep short may not be a thyroid problem. However, such a poor lifestyle is pushing your system and you may eventually develop a thyroid problem as a result. Getting less than seven hours of sleep per night is asking for trouble.


Thyroid-related fatigue starts to show up when you cannot sustain energy long enough, especially when compared to a past level of fitness or ability. If the thyroid foundation is weak, sustaining energy output is difficult. You will notice you just don’t seem to have the energy to do the things you used to be able to do.


The menstrual cycle, pregnancy, exercise, stress, and physical demands are all examples of increased energy demands requiring increased energy output. Thus, PMS is almost always a thyroid problem to a degree. The increased energy demands of the menstrual cycle are simply too much, partly due to an underlying thyroid weakness. Pregnancy is always a major test of the thyroid, as one’s thyroid is called upon to do metabolic work for two bodies. This is why thyroid issues often flare up during or following pregnancy.


Thyroid hormone is synergistic with growth hormone in muscles, and when these two are working properly together then muscles feel fit. Exercise conditions thyroid hormone to work properly to assist general energy production and a lack of exercise contributes to poor thyroid function. The more fit your muscles feel, the less likely thyroid-related fatigue will be an issue for you. If you have poor thyroid function you frequently feel like you don’t have the energy to exercise and usually don’t on a consistent basis. Muscle weakness is a classic hypothyroid symptom.


One of the key symptoms of thyroid fatigue is a heavy or tired head, especially in the afternoon. Thyroid hormone activity is regulated differently in the brain than anywhere else in the body, as brain cells themselves convert T4 to T3 (active thyroid hormone). Your head is a very sensitive indicator of thyroid hormone status. This is different than low blood sugar symptoms from not having eaten for a while. The head just feels sluggish or tired, lacking clarity or sharpness. When this head tiredness occurs too many hours in the day then you will feel like you want to sleep all the time and you will feel depressed, signs of more advanced thyroid-related fatigue.


Another key sign of thyroid fatigue is conking out as soon as you sit down and don’t actually have to do something (there is no necessity making you have to do something). In this case it feels like your body is a car idling too slowly at a stop sign and it just stalls and goes to sleep. This is a clear sign of thyroid fatigue.


You either do or don’t have the symptoms of thyroid-related fatigue. If you wake up energized, maintain decent energy throughout the day, are able to maintain mental alertness/sharpness, have energy as needed to meet demands, and your muscles feel fit, you do not have thyroid-related fatigue. The more you don’t feel this way, the greater the problem. No lab test is needed. In many cases thyroid lab tests may still be normal, even though you clearly are not. The symptoms tell the story and they never lie.

Tuesday, January 24, 2012

STUDY: c-KIT receptor expression is strictly associated with the biological behaviour of thyroid nodules

A large amount of information has been collected on the molecular tumorigenesis of thyroid cancer. A low expression of c-KIT gene has been reported during the transformation of normal thyroid epithelium to papillary carcinoma suggesting a possible role of the gene in the differentiation of thyroid tissue rather than in the proliferation.


The initial presentation of thyroid carcinoma is through a nodule and the best way nowadays to evaluate it is by fine-needle aspiration (FNA). However many thyroid FNAs are not definitively benign or malignant, yielding an indeterminate or suspicious diagnosis which ranges from 10 to 25% of FNAs.



BRAF mutational analysis is commonly used to assess the malignancy of thyroid nodules but unfortunately it still leaves indeterminate diagnoses. The development of molecular initial diagnostic tests for evaluating a thyroid nodule is needed in order to define optimal surgical approach for patients with uncertain diagnosis pre- and intra-operatively. 





Methods: In this study we extracted RNA from 82 FNA smears, 46 malignant and 36 benign at the histology, in order to evaluate by quantitative Real Time PCR the expression levels of c-KIT gene. 



Results: We have found a highly preferential decrease rather than increase in transcript of c-KIT in malignant thyroid lesions compared to the benign ones. To explore the diagnostic utility of c-KIT expression in thyroid nodules, its expression values were divided in four arbitrarily defined classes, with class I characterized by the complete silencing of the gene. Class I and IV represented the two most informative groups, with 100% of the samples found malignant or benign respectively.  The molecular analysis was proven by ROC (receiver operating characteristic) analysis to be highly specific and sensitive improving the cytological diagnostic accuracy of 15%. 



Conclusion: We propose the use of BRAF test (after uncertain cytological diagnosis) to assess the malignancy of thyroid nodules at first, then the use of the c-KIT expression to ultimately assess the diagnosis of the nodules that otherwise would remain suspicious. The c-KIT expression-based classification is highly accurate and may provide a tool to overcome the difficulties in today's preoperative diagnosis of thyroid suspicious malignancies.

Authors:  Sara TomeiChiara MazzantiIvo MarchettiLeonardo RossiKatia ZavagliaFrancesca LessiAlessandro ApolloPaolo AretiniGiancarlo Di CoscioGeneroso Bevilacqua



Credits/Source: Journal of Translational Medicine 2012, 10:7

Sunday, January 22, 2012

Thyroid Surgery Overview: Move Over Frankenstein!

Thyroid surgery is performed in a number of circumstances, including when cancers are found, when enlargement causes cosmetic or respiratory problems, when other forms of treatment are ineffective, and when a pregnant woman's hyperthyroidism cannot be controlled by other means.

In most cases, surgery of the thyroid is not highly complicated, and usually takes no more than two hours. It is frequently performed on an outpatient or overnight basis, with general anesthesia.

There are few complications that result, but when they do, they typically fall into one of two categories: damage to the voice box and / or vocal cords, or damage to the parathyroid glands. If there is damage to the parathyroid glands, this will affect the levels of calcium in the blood, however, this is very rare.


 There are three main types of thyroid surgery:

  1.  Total Thyroidectomy -- complete removal of the thyroid.
  2.  Subtotal Thyroidectomy -- removal of half of the gland
  3.  Thyroid Lobectomy -- removal of only about a quarter of the gland 

Thyroid Gland Removal


Definition: Thyroid gland removal is surgery to remove all or part of the thyroid gland. 
  • Total thyroidectomy removes the entire gland.
  • Subtotal or partial thyroidectomy removes part of the thyroid gland. 
The thyroid gland is part of the endocrine system and plays a major role in regulating the body's metabolism.

Alternative Names:
  • Total thyroidectomy
  • Partial thyroidectomy
  • Thyroidectomy

 Description: Thyroidectomy is done while you are under general anesthesia (unconscious and pain-free). Sometimes it is done with regional anesthesia (awake, but pain-free). The surgeon makes a cut in the neck and locates the gland. All or part of the thyroid gland, depending on the particular procedure, is removed.

Why is the Procedure  Performed?
  • Hyperthyroidism (overactive thyroid)
  • Thyrotoxicosis
  • Hypothyroidism (underactive thyroid) with enlargement of the gland
  • Thyroid Cancer
  • Thyroid swelling (nontoxic goiter)
  • Hashimoto's disease (a type of hypothyroidism)
 The procedure may also be done if a patient with hyperthyroidism does not want to have radioactive iodine treatment and cannot be treated with anti-thyroid medications.

Surgical Risks 

Risks for any anesthesia include the following:
  • Reactions to medications
  • Problems breathing

Risks for any surgery include the following:
  • Bleeding
  • Infection
Additional risks for thyroidectomy include the following:
  •  Bleeding and possible airway obstruction
  • Temporary or permanent loss of ability to speak due to paralysis of the vocal chords
  • Inadequate thyroid function (hypothyroidism)
  • Injury to the adjacent parathyroid glands
  • Inadequate level of calcium in the blood known as hypocalcemia.

 Outlook (Prognosis)

When performed by experienced endocrine surgeons, the outcome of thyroid surgery is usually excellent. Thyroid function tests may need to continue following thyroid surgery, and thyroid hormone replacement maybe necessary.

Recovery

In general, patients recover rapidly from uncomplicated thyroid surgery. Most patients are able to resume most normal activities within 1-2 weeks.

Reviewed By: J.A. Lee, M.D., Assistant Professor of Surgery, Columbia University Medical Center, New York, NY. Review provided by VeriMed Healthcare Network.

  

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites.

Saturday, January 21, 2012

What Causes Thyroid Cancer ?



 Although scientists have found that thyroid cancer is linked with a number of other conditions (described in  "What are the risk factors for thyroid cancer?"), the exact cause of most thyroid cancers is not yet known. Researchers have made great progress in understanding how certain changes in a person's DNA can cause thyroid cells to become cancerous. 
  • DNA is the chemical in each of our cells that makes up our genes – the instructions for how our cells function. We usually look like our parents because they are the source of our DNA. However, DNA affects more than how we look. It also can influence our risk for developing certain diseases, including some kinds of cancer.
  • Some genes contain instructions for controlling when our cells grow and divide. Certain genes that speed up cell division or cause cells to live longer than they should are called oncogenes. Others that slow down cell division or cause cells to die at the appropriate time are called tumor suppressor genes. Cancers can be caused by DNA changes that turn on oncogenes or turn off tumor suppressor genes.
  • People inherit 2 copies of each gene – one from each parent. People can inherit damaged DNA from one or both parents, which accounts for inherited cancers. Most cancers, though, are not inherited. In these cases, a person's DNA is damaged by exposure to something in the environment, like smoking or radiation. Other DNA changes may just be random events that sometimes happen inside a cell, without having an external cause.
Papillary Thyroid Cancer:  Several DNA mutations have been found in some forms of papillary thyroid cancer. Many of these cancers have changes in specific parts of the RET gene. The altered form of this gene, known as the PTC oncogene, is found in about 10% to 30% of papillary thyroid cancers overall, and in a larger percentage of these cancers found in children and/or linked with radiation exposure. These RET mutations usually are acquired during a person's lifetime rather than being inherited. They are present only in cancer cells and are not passed on to the patient's children.
  • Many (30% to 70%) papillary thyroid cancers contain a mutation of the BRAF gene. The BRAF mutation is less common in thyroid cancers in children and in those thought to arise from exposure to radiation. Cancers with BRAF changes tend to have more aggressive growth and a greater likelihood of spreading to other parts of the body. 
  • Both BRAF and RET/PTC changes are thought to cause cells to grow and divide. It is extremely rare for papillary cancers to have changes in both the BRAF and RET/PTC genes. Some doctors now advise testing papillary cancer samples for these gene mutations, as some studies have suggested they may affect a person's prognosis (outlook). 
  • Changes to other genes have also been tied to papillary thyroid cancer, including those in the NTRK1 gene and the METgene.
Follicular Thyroid Cancer:  Acquired changes in the RAS oncogene have a role in causing some follicular thyroid cancers.

Anaplastic Thyroid Cancer:  These cancers tend to have some of the mutations described above and often have changes in the p53 tumor suppressor gene and the CTNNB1 oncogene as well.

Medullary Thyroid Cancer:  People who have medullary thyroid carcinoma (MTC) have mutations in different parts of the RET gene compared with papillary carcinoma patients. Nearly all patients with the inherited form of MTC and about 1 of every 10 with the sporadic (non-inherited) form of MTC have a mutation in the RET gene.
  • Most patients with sporadic MTC have acquired mutations present only in their cancer cells. Those with familial MTC and MEN 2 inherit the RET mutation from a parent. These mutations are present in every cell of the patient's body and can be detected by testing the DNA of blood cells.
  • In people with inherited mutations of RET, one RET gene is usually normal and one is mutated. Because every person has 2RET genes but passes only one of them to a child (the child's other RET gene comes from the other parent), the odds that a person with familial MTC will pass a mutated gene on to a child are 1 in 2 (or 50%).


Last Medical Review: 06/29/2011
Last Revised: 01/20/2012

Wednesday, January 18, 2012

Cancer According to the Dictionary

When we hear the words, "You have cancer" the world suddenly stops and we can barely hear anything else. Then when it's time to digest the diagnosis we may still not really know what is cancer. Here we discuss a very basic and general definition of cancer.


Definition of Cancer: 


Throat, Lung, Breast, Stomach, Bowel, Bladder, Prostate, Testicular, Skin Cancer


NOUN: Any of various malignant neoplasms characterized by the proliferation of, anaplastic cells that tend to invade, surrounding tissue and metastasize to new body sites. 1. The pathological condition characterized, by such growths. 2. A pernicious, spreading evil: A cancer of bigotry spread through the community. Characteristics of Cancer 



Abnormality:  Cells are the structural units of all living things. Each of us has trillions of cells, as does a growing tree. Cells make it possible for us to carry out all kinds of functions of life: the beating of the heart, breathing, digesting food, thinking, walking, and so on. However, all of these functions can only be carried out by normal healthy cells. Some cells stop functioning or behaving as they should, serving no useful purpose in the body at all, and become cancerous cells. 




Invasiveness:  Sometimes tumors do not stay harmlessly in one place. They destroy the part of the body in which they originate and then spread to other parts where they start new growth and cause more destruction. ;This characteristic distinguishes cancer from benign growths, which remain in the part of the body in which they start. Although benign tumors may grow quite large and press on neighboring structures, they do not spread to other parts of the body. Frequently, they are completely enclosed in a protective capsule of tissue and they typically do not pose danger to human life like malignant tumors (cancer) do. 




A group of diseases: Although cancer is often referred to as a single condition, it actually consists of more than 100 different diseases. These diseases are characterized by uncontrolled growth and spread of abnormal cells. Cancer can arise in many sites and behave differently depending on its organ of origin. Breast cancer, for example, has different characteristics than lung cancer. It is important to understand that cancer originating in one body organ takes its characteristics with it even if it

spreads to another part of the body. 

For example, metastatic breast cancer in the lungs continues to behave like breast cancer when viewed under a microscope, and it continues to look like a cancer that originated in the breast. 

Uncontrollability: The most fundamental characteristic of cells is their ability to reproduce themselves. They do this simply by dividing. One cell becomes two, the two become four, and so on. The division of normal and healthy cells occurs in a regulated and systematic fashion. In most parts of the body, the cells continually divide and form new cells to supply the material for growth or to replace worn-out or injured cells. For example, when you cut your finger, certain cells divide rapidly until the tissue is healed and the skin is repaired. They will then go back to their normal rate of division. In contrast, cancer cells divide in a haphazard manner. The result is that they typically pile up into a non-structured mass or tumor. 

Sunday, January 15, 2012

Faces of Thyroid Cancer: Stefanie Raab



MAINEVILLE, Ohio - A distinctly planted row of American flags waved in unison under the bright sunlight as nine soldiers from the 943rd Engineer Detachment rolled in from Afghanistan. 


"You know this country is the greatest country on Earth. And why is that? Because of soldiers like you!" could be heard throughout the hall at the Kings Mills U.S. Army Reserve Center Sunday afternoon. 

The front gate decorated with “Welcome Home” signs started to open, sliding past the gravel path. Two vans, full of soldiers, made their way passed the chain link fence-type gate. 

They unloaded from the full-sized white vans and walk passed Veterans who thanked them for their service, shaking their hands. But it’s inside the Reserve Center that these soldiers are anxious to get to. That’s where their families wait. 

"The Army makes our nation strong. Soldiers make our Army strong. Families make our soldiers strong,” said an uniformed man inside. 

The nine soldiers walked in. They are greeted with loud whistles, clapping and cheering—as well as some tears, and a lot of hugs and kisses. 

"Welcome home! Welcome home 943rd! Welcome home!" 

Cpl. Peter Raab was deployed for 10 months. Walking in was overwhelming for the husband and father. 

"It was a relief to actually be able to see my wife, my son, my family." 

His 3-year-old son William has been waiting to tell his daddy something that he learned just for his return. 

Securely within his father’s arms, he moved his tiny hand over his heart, "...for which it stands. One nation, under God, indivisible, with liberty and justice for all." 

Army wife, Stefanie Raab played the role of both parents for nearly a year, she said. 

"It's definitely hard. You miss him a lot." 

Even harder when, while her husband was in Afghanistan, Stefanie was diagnosed with thyroid cancer. It was something no one was expecting, especially her husband who was an ocean away from his wife. 

"It was a shocker. You know, definitely being away from my wife and my two kids in an environment where anything can happen—and all of a sudden you get that news that the person you love the most just got cancer," said Peter. 

He was able to take a two-week leave to be there for her surgery in May. And since that surgery, she has been cancer-free. 

The two, who are so close now, didn't start out even liking each other. 

"We worked in the pediatric department together, and he drove me absolutely insane," said Stefanie, holding her husband’s hand. 

"One day, my dad brought my oldest child [Laney] up to have lunch with me, and she saw him and she liked him. She said, 'You should go on a date with him.'" 

That fifth-grade matchmaker could not be at the reunion at the Reserve Center in Maineville because she had a basketball game to win in Northern Kentucky—plus the 11-year-old thought her dad is due to return from Afghanistan next month. 

All the way on the other side of the Tri-State in Edgewood, Ky., the Beechwood Tigers got ready to take the floor battling St. Pius X. 

No. 53, Laney Raab, dribbled her way to the 2-point line, took her shot… nothing but net. It was drills and she was gearing up for her last game of the season. 

As the game was about to start, both teams gather by the scoreboard. Laney’s coach took the microphone and announced a special guest… returning from Afghanistan. 

Laney’s face lit up, eyes wide—confused, however, because Peter has yet to walk through the gym doors. She looked all around her, then he walked in, pink roses in hand. 

She immediately pounded the hardwood floor to get to his arms as fast as she could. 

They embraced, Laney sobbing in his camouflaged chest. 

“I’m here, I’m back… I’m not going anywhere,” the father assured his young daughter. “I love you.” 

“I love you too,” she told him. 

The crowd cheered, many with tears in their eyes for the second reunion of the day. 

As the game commenced, Beechwood grabbed the ball from the start. It was evident that an emotional start gave Laney the upper hand—scoring the first points of the game, leaving the crowd standing and cheering.

Thyroid Cancer: Risk Factors and Prevention


Thyroid cancer is the fastest increasing newly diagnosed cancer worldwide regardless of age, sex, race or ethnic background. According to the Mayo Clinic the number of people diagnosed with the condition is rising is rising.  Women are three times more likely than men to be diagnosed with the condition and sadly, childhood cancer survivors are also at an increased risk. The National Cancer Instituted noted that during the year 2011, an estimated 36,550 women were diagnosed with thyroid cancer in the USA, compared to 11,470 men.
RISK FACTORS:  Columbia University Medical Center noted that 20 to 25 percent of patients with medullary thyroid cancer and 5 percent of patients with papillary thyroid cancer have a family member who had thyroid cancer.
One type of medullary thyroid cancer, MEN 2A associated medullary thyroid cancer, usually results from a mutation of the gene RET proto-oncogene. Another type of medullary thyroid cancer, familial medullary thyroid cancer, is passed down through families.
Another genetic condition that increases the risk of thyroid cancer is familial adenomatous polyposis, a condition in which the patient develops multiple benign polyps in her colon that will become malignant if not removed. Cetta et al. noted that papillary thyroid cancer is a rare manifestation of familial adenomatous polyposis.
Exposure to radiation is another risk factor of thyroid cancer, such as radiation therapy that is targeted to the neck. Before the link between radiation and thyroid cancer was known, radiation was used to treat many benign diseases.
MedlinePlus noted that people who had radiation therapy during childhood have an increased risk of thyroid cancer. People exposed to radiation through nuclear plant accidents or nuclear weapons also have a higher risk of developing thyroid cancer.
People who have either had a goiter or who have a family history of goiters also have an increased risk of developing thyroid cancer. A goiter is a noncancerous enlargement of the thyroid gland. Goiters may occur for unknown reasons.
People who do not get enough iodine in their diet may develop colloid goiters, or endemic goiters. MedlinePlus stated that on some occasions, medications such as aminoglutethimide and lithium can cause nontoxic goiters, or sporadic goiters.
PREVENTION: While there is no way to prevent thyroid cancer, people at risk can take certain precautions. For example, the MayoClinic.com noted that people with the genetic mutation that puts them at increased risk for medullary thyroid cancer may choose to have a prophylactic thyroidectomy. Prophylactic thyroidectomy is surgery on the thyroid gland done to prevent medullary thyroid cancer.
In cases of a radiation emergency, people at risk, such as people living near a nuclear power plant, may take potassium iodine to prevent the thyroid gland from taking in radioactive iodine released in the air. The Centers for Disease Control and Prevention warned that potassium iodine is only taken when advised by a physician, emergency management official or public health official.
REFERENCES:
  • Cetta F, Curia MC, Montalto G, Gori M, Cama A, Battista P and Barbarisi A. “Thyroid Carcinoma Usually Occurs in Patients with Familial Adenomatous Polyposis in the Absence of Biallelic Inactivation of the Adenomatous Polyposis Coli Gene.” The Journal of Clinical Endocrinology and Metabolism, January 2000. Web. 10 January 2012 
    • Centers for Disease Control and Prevention. Potassium Iodine. Web. 10 January 2012 
    Reviewed January 10, 2011
    by Michele Blacksberg RN

    Thursday, January 12, 2012

    Understanding Thyroid Gland Diagnostic Tests

    Diagnostic testing for thyroid health involves evaluation of blood work

    Thyroid Gland Review


    The thyroid gland is a vitally important hormonal gland, which mainly works for body’s metabolism. It is located in the front part of the neck below the voice box and is butterfly-shaped. The functions of the thyroid gland include the production of the thyroid hormones triiodothyronine (T3) and tetraiodothyronine, also called thyroxine (T4).

    The thyroid hormones have a variety of different functions: They regulate metabolism, growth and maturation of the human body.  There you will also find more information on thyroid hyperfunction and hypofunction, and the signs and symptoms of these conditions.
    The production of the thyroid hormones is regulated by the pituitary gland (hypophysis). The pituitary gland produces the thyroid-stimulating hormone (TSH), which not only stimulates the production of thyroid hormones, but also influences the size of the thyroid gland. TSH production, in turn, is inhibited by the thyroid hormones. The system can be compared to a thermostat, which makes sure that room temperature is kept at a set value. This is why the concentration of thyroid hormones in the blood usually is fairly constant. 
    There are different tests to check the functioning of the thyroid gland. We will now explain which ones there are and what they are used for.

    Palpation

    What is a palpation of the thyroid gland?
    After talking with you, the examination the doctor usually does first will be a palpation: he or she will touch the neck with their hands, paying attention to what the thyroid gland feels like and whether it might have enlarged.
    What do the results mean?
    An enlarged thyroid – also called goiter or struma – can indicate a lack of iodine but with thyroid function still in normal range. Yet it can also be a sign of thyroid hyperfunction (too much thyroid hormone production), or of thyroid hypofunction (too little thyroid hormone production). Palpable nodules can also be a sign of a thyroid function problem. But neither enlargement nor nodules necessarily mean that the functioning of the thyroid gland is impaired.

    Blood Tests

    What is a blood test for thyroid hormones?
    The thyroid gland continually releases a certain amount of hormones into the blood. So a blood test can be used to determine the amounts of hormones produced by the thyroid gland.
    The blood test measures TSH and the thyroid hormones triiodothyronine (T3) and thyroxine (T4). A change in the TSH level can be an early detector for a thyroid function problem. This is why often, as a first step, only TSH is measured. If the TSH level in the blood is higher or lower than normal, the thyroid hormones T4 and T3 are also measured. Because most thyroid hormones are bound to certain blood proteins and only free hormones (which are not bound to proteins) act in the body, nowadays only the so-called “free thyroid hormones” (FT3 and FT4 – with “F” standing for “free”) are measured.
    Thyroid antibodies are measured when looking for the cause of a thyroid function problem. Apparently, if our immune system wrongly regards the body’s own thyroid gland cells as foreign substances, it produces thyroid antibodies.
    Another hormone produced by the thyroid gland is calcitonin. Its blood level is not routinely measured. If the calcitonin level in the blood is higher than usual, this can indicate a certain type of thyroid gland cancer, however, if such a disease is already suspected.
    What do the results mean?
    If the amount of thyroid hormones T3 and T4 is too high or too low, there is an imbalance between the thyroid hormones needed by the body and the amount of thyroid hormones available.
    A blood test can measure the following substances:
    • Thyroid-stimulating hormone (TSH): A TSH level that is higher than normal indicates thyroid hypofunction (hypothyroidism), because the pituitary gland produces more TSH in order to stimulate the thyroid gland to produce thyroid hormones. If, on the other hand, there is very little TSH in the blood, this can indicate thyroid hyperfunction (hyperthyroidism). The pituitary gland then tries to balance the excess amount of thyroid hormones by producing less TSH, in order to not stimulate the thyroid gland any more.
    • Free triiodothyronine (FT3) and free thyroxine (FT4): Levels of free thyroid hormones in the blood that are higher than normal can indicate a hyperfunction. If there are not enough thyroid hormones, this can be a sign of a thyroid hypofunction.
    • Thyroid antibodies: The concentration of different thyroid antibodies is raised in certain thyroid disorders, where the body’s immune system works against the thyroid tissue. These disorders include so-called Hashimoto’s thyroiditis and Grave’s disease. A low level of antibodies is associated with a variety of diseases such as an inflammation of the thyroid gland (thyroiditis), type 1 diabetes or rheumatoid arthritis.
    • Calcitonin: The calcitonin level is usually raised in a certain type of thyroid cancer. But it also plays an important role in calcium and bone metabolism and can also be changed in other diseases.
    Many drugs, if they are taken long-term, can also influence the concentration of TSH and thyroid hormones. And pregnancy can also change the hormone concentration in the blood.
    Substances influencing thyroid measurements include:
    • Acetylsalicylic acid or ASA (ASS in German)
    • Cortisone
    • St John's wort
    • Certain water pills containing furosemide
    • Thyroid medications
    For this reason, it is important to inform your doctor about any drugs you take.

    Thyroid Ultrasound

    What is thyroid ultrasound?
    An ultrasound examination (sonography) is used to obtain a picture of the thyroid. To do the examination, a small amount of jelly is put on the transducer of the ultrasound scanner, which is then moved over the neck. This examination uses sound waves that are sent into the part of the body to be examined. Depending on the type of tissue, these sound waves are sent back with different intensities or not at all, or are deviated. The sound waves that are sent back are turned into a spatial image on the monitor of the ultrasound device, so that changes in the tissue and the size of the thyroid gland can be seen. An ultrasound examination has no known adverse effects or risks.
    What do the results mean?
    In an ultrasound examination, enlargement of the thyroid gland can be seen. Changes in the tissue – like cysts or age-related alterations – can also be detected. If the thyroid gland is larger than normal, this may be associated with a thyroid hypofunction or hyperfunction. To say for sure whether the thyroid gland really produces too many or not enough hormones, it is necessary to do an additional blood test, however.
    If nodules are detected in the ultrasound examination, it might be useful to do other examinations like a thyroid scan or, in some cases, magnetic resonance tomography (MRT).

    Thyroid Scan

    What is a thyroid scan?
    A thyroid scan (or thyroid scintigraphy) is used to obtain a picture of the thyroid metabolism. The examination uses a weakly radioactive substance that is injected into an arm vein. The bloodstream carries this substance into every part of the body, but it is the thyroid gland that will take up most of it. Depending on how intensely or how weakly the thyroid gland is working, a larger or lesser amount of the substance will build up in the thyroid tissue. The thyroid scan can create a picture of the distribution and the amount of this weakly radioactive substance. This picture is called a scintigram.
    It may be necessary to stop taking certain drugs before having a thyroid scan, for example thyroid medications. It is therefore important to talk to your doctor before the examination about which drugs you take.
    A scintigraphy can have adverse effects. In rare cases, the needle can damage blood vessels or nerves, or the puncture can become inflamed. Allergic reactions, particularly against the substance injected, are possible.
    What is more, people who have this examination done are exposed to radiation. Only small amounts of radioactive substances are used, however, and they will decay in the body in a few days.

    What do the results mean?
    A thyroid scan examines the activity of the thyroid gland: The more the thyroid gland works, the more blood goes through it and the more of the injected substance builds up in the tissue. On the image, the active areas have brighter or different colors than the non-active ones.
    Depending on how much of the injected substance builds up, the areas are called cold nodules or hot nodules.
    If less substance with a radioactive tracer is built up in one area, this nodule is called “cold”. Compared to the surrounding area, the metabolism of this tissue is less active. In most cases, a cold nodule indicates harmless changes in the tissue. Even if there is less metabolism in the area of the nodule, this usually does not lead to a lack of thyroid hormones, because the remaining tissue makes up for it by producing more hormones. In very rare cases, a cold nodule can also be a thyroid tumor.
    In the “hot” nodules, which produce many hormones, on the other hand, more substance with the radioactive tracer builds up – the metabolism is more active. From a certain size, hot nodules can lead to thyroid hyperfunction. 

    Fine Needle Aspiration

    What is a thyroid fine needle aspiration?
    For a thyroid fine needle aspiration a fine, thin needle is put into the thyroid tissue to withdraw tissue or fluid. It is usually not necessary to use an anesthetic, because the examination is not more unpleasant than having a normal blood sample taken from the arm. For better orientation, doctors often additionally use an ultrasound scanner.
    In rare cases, the place where the needle was put in can become bruised or inflamed after the examination. If you take medication that stops the blood from clotting (anticoagulants), it is important to talk to your doctor about whether it is necessary to stop taking it before having fine needle aspiration.
    What do the results mean?
    Thyroid fine needle aspiration can give additional clues about whether the changes are benign or malignant (cancerous). The cells of the tissue samples taken are tested in a laboratory. A fine needle can also be used to empty fluid-filled cysts. It is also possible to detect an inflammation of the thyroid tissue.
    Next planned update: June, 2014. You can find out more about how our health information is updated here.

    References

    • Bruhn HD, Fölsch UR, Schäfer H. LaborMedizin – Indikationen, Methodik und Laborwerte – Pathophysiologie und Klinik.Stuttgart: Schattauer-Verlag. 2008.
    • Cooper DS. Hyperthyroidism. Lancet 2003; 362: 459-468.
    • Dayan CM. Interpretation of thyroid function tests. Lancet 2001; 357: 619-624.
    • Kharlip J, Cooper DS. Recent developments in hyperthyroidism. Lancet 2009; 373: 1930-1932.
    • Mehanna HM, Jain A, Morton RP, Watkinson J, Shaha A. Investigating the thyroid nodule. BMJ 2009; 338: 705-709.

    SOURCE: German Institute for Quality and Efficiency in Health Care (IQWiG).
    Created: May 24, 2011  Last Update: July 6, 2011.