1. Hyperthyroidism Slideshow Pictures
2. Take the Thyroid Disorder Quiz
3. Thyroid Symptoms and Solutions Slideshow Pictures

Medical Author:

Ruchi Mathur, MD, FRCP(C)

Ruchi Mathur, MD, FRCP(C)

Ruchi Mathur, MD, FRCP(C) is an Attending Physician with the Division of Endocrinology, Diabetes and Metabolism and Associate Director of Clinical Research, Recruitment and Phenotyping with the Center for Androgen Related Disorders, Department of Obstetrics and Gynecology at Cedars-Sinai Medical Center.

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Medical Editor:

William C. Shiel Jr., MD, FACP, FACR

William C. Shiel Jr., MD, FACP, FACR

Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.

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In this Article

• Introduction to thyroid disease
• Thyroid 101: What is the thyroid and what does it do?
• What types of thyroid disease can occur when the function of the thyroid is affected?
• What signs and symptoms can occur if thyroid function is affected?
• What types of thyroid disease can occur when the structure of the thyroid is affected?
• What signs and symptoms can occur if thyroid structure is affected?
• How is the diagnosis of thyroid disease made?
• What is the treatment for thyroid disease?
• What is the outlook for someone with a thyroid disease?
• Thyroid Disease At A Glance
• Thyroid FAQs
• Patient Comments: Thyroid Disease - Describe Your Experience
• Patient Comments: Thyroid Disease - Treatment
• Patient Comments: Thyroid Disease - Symptoms and Signs
• Find a local Endocrinologist in your town
• Thyroid Disease Index

Blood tests

Blood tests are often used to help determine thyroid function. Thyroid stimulating hormone (TSH) is often a screening tool and can be used along with serum T3 and T4 levels. If these hormones are abnormal, and further information regarding a possible cause is needed, antibody levels in the blood can be checked. Depending on the clinical situation, your doctor may look for specific antibodies such as:

• Antithyroglobulin antibodies
  
  
• Anti TPO antibodies
  
  
• TSH receptor stimulating antibodies
  
  
• If cancer is suspected, a thyroglobulin level may be ordered, and in rare circumstances, a calcitonin levels may be checked.

Imaging

If there is concern about the structure of the gland, if size needs to be quantified or if there is a suspicion of cancer, imaging tests may be performed. Common modes of imaging include an ultrasound of the thyroid gland and radioiodine scanning and uptake. The ultrasound helps show size and consistency of the gland (for example, it is good at detecting cysts or calcifications within a gland), but it cannot always tell a benign gland from a cancerous gland. Ultrasounds may be done in a doctor's office or in a hospital Radiology department.

Thyroid scans involve the use radioactively labeled form of iodine and are usually performed the Radiology department of a hospital or clinic. Since the thyroid is the only tissue in the human body that picks up iodine, the scan is very specific for finding thyroid tissue. If the thyroid is not picking up iodine normally, "spots" show up on the scan. A "cold" spot implies that the tissue is not picking up enough iodine compared to the rest of the gland. This may be seen in nonfunctioning nodules and may also be a sign of malignancy.

A "hot" spot implies that the tissues in that area is taking up more iodine than the surrounding tissue, and is overactive. This may be seen in a toxic nodule. Hot spots are rarely ever cancerous. In addition, there are comparison values to determine what normal thyroid uptake should be. A normal thyroid picks up 8%-35% of the administered dose of iodine within 24 hours. If values above or below this range is seen, it may point to underlying thyroid disease.

Biopsy

A biopsy provides a tissue sample for a pathologist to look at. This is usually the gold standard, especially when looking for diseases such as cancer. Thyroid biopsies are usually performed using a fine need to aspirate cells from the gland. This is often referred to as fine needle aspirate or an FNA. FNAs can be done in a doctor's office or in a clinic setting, and may involve an ultrasound machine to help guide the needle. Tissue samples can also be obtained during surgery. An FNA is a safe easily performed procedure, however, depending on the skill of the person performing the procedure, there is a chance that the aspiration may not yield enough tissue, or that the sampling is not of the right area.