Download Thyroid Glossary - YOUR THYROID And YOU

Thyroid Glossary -
July 2009
Ablation - surgical removal of the thyroid gland (a total thyroidectomy).
Abnormal - Not normal. Deviating from the usual structure, position, condition, or behaviour.
Alopecia - Loss of hair; baldness in areas where hair is usually present.
Anaemia - A condition in which the number of red blood cells is below normal.
Antibody - A type of protein made by certain white blood cells in response to a foreign substance. Antibodies that
attack the body's own proteins are called autoantibodies.
Antithyroid drug - Used to treat hyperthyroidism in order to reduce the excessive thyroid activity by hindering
production of thyroid hormones. (Examples: propylthiouracil (PTU), methimazole (Tapazole®), and carbimazole).
AO - (Adult Onset) Medical or health issues that become evident only in adulthood.
Apnea - Temporary absence of breathing. Sleep Apnea which occurs while sleeping.
Arrhythmia - An irregular pulse or abnormal heartbeat.
Artrial Fibrillation - Common heart arrythmia with rapid beating in upper chambers.
Asymptomatic -Having no signs or symptoms of disease.
Atypical - Not typical ; not like the usual or normal type.
Autoantibody - An antibody that has wrongly identified tissue/cells as foreign matter, then proceeds to attack
those organs.Top of Form 1 Antibodies that attack the body's own proteins are called autoantibodies.
Autoimmune Disease - A condition in which the body recognizes its own tissues as foreign and directs an immune
response (attack) against them.
Benign - Not cancer. Not malignant.
Biopsy - The removal of cells or tissues for examination under a microscope.
Blood pressure - The pressure of the blood within the arteries.
Bradycardia - Excessive slowness in the action of the heart, usually with a heart rate below 60 beats per minute.
CAT scan, CT scan - A series of detailed pictures of areas inside the body taken from different angles; the
pictures are created by a computer linked to an x-ray machine.
Cognitive Impairment - (Brain Fog) General loss of mental or cognitive ability. Sluggish metal capacity and memory.
Cold Sensitivity - Feeling cold or sensitivity to the cold.
Constipation - Irregular and infrequent or difficult evacuation of the bowels.
Depression - A mental state of depressed mood characterised by feelings of sadness, despair and discouragement.
Dermopathy - Any disease of the skin.
Diagnosis - The process of identifying a disease by the signs and symptoms.
Diarrhea - Unusually frequent or unusually liquid bowel movements.
Diffuse - Lacking a distinct border, not localized, spread out.
Diplopia - Double vision.
Dysphagia - Difficulty in swallowing or inability to swallow.
Dysplasia - Cells that look abnormal under a microscope but are not cancer.
Dyspnea - Difficult or laboured breathing.
Edema – The swelling of soft tissues as a result of excess fluid accumulation.
Euthyroid - The state of having normal thyroid gland function.
Exophthalmos - Protrusion of one or both eyes, usually associated with Graves disease.
Eye Inflammation - Inflammation of the orbit of the eye, usually associated with Graves disease.
Fatigue - Excessive tiredness or weakness.
FNA - (Fine needle aspiration) The use of a thin needle to withdraw material from the body. For example, this
method is commonly used to determine whether a nodule in the thyroid gland is benign or malignant. A fine gauge
needle is placed into the nodule and a drop of blood is withdrawn. The cells are studied under the microscope by a
pathologist.
FSH - The Follicle Stimulating Hormone; a gonadotrophin secreted by the pituitary gland, the hormone promotes
fertility in men and helps to regulate the menstrual cycle in women.
FT3 - Reflects the biologically active free form of T3. FT3 is typically elevated to a greater degree in Graves'
disease and in toxic adenomas. It may also be important in monitoring patients on antithyroid therapy. Occasionally,
FT3 alone is elevated in about 5 percent of the hyperthyroid population.
FT4 - (Free Thyroxine) Free T4 measures the fraction of T4 that is not bound by thyroxine binding proteins and is
biologically active. FT4 are elevated to a greater degree in toxic multinodular goitre, excessive T4 therapy, and
hyperthyroidism. Low levels of FT4 may indicate hypothyroidism and other thyroid health issues.
GH - The Growth Hormone, secreted by the pituitary gland; one of the hormones responsible for normal bone
development and teenage growth.
Glucagon Test - An alternative to the insulin tolerance test; used to test for normal function of the hypothalamus
and pituitary gland; glucagon increases blood sugar levels, causing a number of hormones to be released in response.
Goitre - Enlargement of the thyroid gland.
Graves' Disease - An autoimmune disorder of the thyroid gland that causes excessive production and release of
thyroid hormone, the most common form of Hyperthyroidism.
Hair Loss - Loss or thinning of head or body hair.
Hashimoto's thyroiditis - An autoimmune disorder of the thyroid gland in which the body's immune system attacks
the thyroid gland, destroying the cells of the thyroid gland.
HDL - High-density lipoproteins, the smallest and densest lipoproteins, contain a high proportion of protein. HDL
can remove cholesterol from the arteries, so they are seen as "good" lipoproteins
Heart rate - The number of heart beats, usually per minute. (Abbreviated HR)
Heat Sensitivity - Feeling warm or sensitivity to the heat.
Heterogeneous - Composed of varied cell types.
Homogeneous - Composed of identical cell types.
Hydrocortisone - The main glucocorticoid secreted by the Adrenal Cortex. Synthetic versions of this are used to
relieve the symptoms of certain hormone shortages and to suppress an immune response.
Hypertension - Abnormally high blood pressure.
Hyperthyroid - Excess of thyroid hormone resulting from an overactive thyroid gland. Also called overactive
thyroid.
Hypothermia - Low body temperature.
Hypothyroid - Deficiency of thyroid hormone which is normally made by the thyroid gland. Also called underactive
thyroid.
Immunodeficiency - The decreased ability of the body to fight infection and disease.
Immunoglobulin - A protein produced by plasma cells and lymphocytes. *Different classes of Immunoglobulins:
immunoglobulin A (IgA), immunoglobulin G (IgG), immunoglobulin M (IgM), immunoglobulin D (IgD) and
immunoglobulin E (IgE).
Immunosuppressive drug - Prescribed medicines that decrease the function and activities of the immune system.
(Example: cyclosporine)
Insomnia - Difficulty falling asleep or staying asleep for long enough.
Insulin - A hormone made by the islet cells of the pancreas. Insulin controls the amount of sugar in the blood by
moving it into the cells, where it can be used by the body for energy.
Insulin resistance - Diminished effectiveness of insulin in lowering blood sugar levels. It is usually due to insulin
binding by antibodies.
Iodine - An essential element in the diet used by the thyroid gland to make thyroid hormones. It is found in
shellfish and iodized salt.
LDL - Low-density lipoproteins that carry cholesterol around the body, for use by various cells. Increased levels
are associated with atherosclerosis, and thus myocardial infarctions and strokes. This is why cholesterol inside
LDL lipoproteins is called bad cholesterol.
Levothyroxine - A synthetic thyroid hormone used as a thyroid hormone replacement drug,
LH - The Luteinizing Hormone; a gonadotrophin secreted by the pituitary gland, the hormone promotes masculinity
in men and helps to regulate the menstrual cycle in women in conjunction with FSH.
Local - Confined to one specific area.
Lymphocytes - a type of white blood cell.
Medullary thyroid carcinoma - Cancer that develops in C cells of the thyroid. It comprises less than 10% of all
thyroid cancers and tends to be of familial origin. Patients usually present with a thyroid nodule that is painless
and firm. Surgery is the preferred treatment as it is generally not very sensitive to radiation and almost
unresponsive to chemotherapy.
Metabolism - The total of all chemical changes that take place in a cell or an organism. These changes produce
energy and basic materials needed for important life processes.
MRI Scan - Magnetic Resonance Imaging. MRI is a scanning device that uses a magnetic field, radio waves, and a
computer. Signals emitted by normal and diseased tissue during the scan are assembled into a image.
MVP - (Mitral valve prolapse) A valvular heart disorder in which one or both mitral valve flaps close incompletely
during systole usually producing either a click or murmur.
Myopathy - Abnormal functioning of the muscles marked by weakness of involved muscles and limbs.
Myxedema - A type of edema associated with hypothyroidism. It is characterized by the accumulation of
mucoproteins in tissue fluid.
Neuropathy - A disorder affecting the cranial nerves or the peripheral nervous system. It is manifested with pain,
tingling, numbness, and muscle weakness.
Nodular thyroid disease - Characterized by areas of overactivity within the thyroid gland, known as thyroid
nodules.
Nodule - Lumps which commonly arise within an otherwise normal thyroid gland.
Ophthalmologists - Physicians who devote their practice to eyes and their disorders.
Ophthalmology - The study of the eye and its associated parts.
Ophthalmopathy - Any eye disease.
Palpitations - Unpleasant sensations of irregular and/or forceful beating of the heart.
Paresthesia - Abnormal sensations, such as burning, prickling.
Pericardial Effusion - Fluid collection within the pericardial sac that surrounds the heart, usually due to
inflammation.
Pericarditis - Inflammation of the membrane surrounding the heart.
Peripheral - On or near an edge or constituting an outer boundary; the outer area.
Pernicious anemia - A blood disorder caused by inadequate vitamin B12 in the blood.
Photophobia - Abnormal sensitivity to light, especially: painful sensitiveness to strong light.
Pleural effusion - Excess fluid between the two membranes that envelop the lungs.
Postpartum thyroiditis - Inflammatory condition of the thyroid, occurs in 5%-9% of women following childbirth.
Although the hypothyroidism associated with it is usually temporary, it can become permanent in up to one third of
affected women.
Pretibial myxedema - Skin condition characterized by swollen, itchy patches of skin on the front of the lower legs
or shins. This condition is associated with Graves' disease.
Primary Amenorrhoea - The inability to menstruate, caused by a failure of sexual maturation and function.
Prognosis - The probable outcome or course of a disease; the chance of recovery.
Progression - Increase in the size of a tumor (such as with cancer) or spread of disease in the body.
PTU - Propylthiouracil, an antithyroid medication, a drug that blocks the production of thyroid hormone.
Pulmonary - Relating to the lungs.
Radioactive iodine - Used in diagnostic tests as well as in radiotherapy of a hyperactive thyroid gland
(hyperthyroidism), most often due to Graves’ disease.
Radioactive iodine uptake - A special test used to diagnose thyroid disease. During this procedure, the amount of
iodine "taken up" by the thyroid is measured and images of the thyroid gland are taken.
Rash - Breaking out (eruption) of the skin.
Red blood cell - (RBC) A cell that carries oxygen to all parts of the body.
Remission - The disappearance of symptoms.
Scintigraphy - (Radionuclide imaging) A test that produces pictures (scans) of internal parts of the body. The
person is given an injection or swallows a small amount of radioactive material; a machine called a scanner then
measures the radioactivity in certain organs.
Subacute - Rather recent onset or somewhat rapid change.
Subacute thyroiditis - Inflammatory condition of the thyroid of unclear origin, often follows an upper respiratory
infection. The hyperthyroidism and hypothyroidism associated with it is usually mild and temporary.
Subtotal thyroidectomy - A surgical procedure during which part of the thyroid gland is surgically removed.
Systemic - Circulating throughout the body.
T3 - (Triiodothyroninine) A form of thyroid hormone in the bloodstream, T3 is biologically active.
T4 - (Thyroxine) A form of thyroid hormone in the bloodstream. Most thyroid hormone in the blood is T4;
however, it is not biologically active in the body. Special cells convert T4 into T3.
Tachycardia - Excessive rapidity in the action of the heart, usually with a heart rate above 100 beats per minute.
Tg - (Thyroglobulin) The form that thyroid hormone takes when stored in the cells of the thyroid.
TG - (Triglycerides) Fats composed of three fatty acid chains linked to a glycerol molecule.
Thyroid hormones - General term used for hormones made by the thyroid gland, the two most important are
thyroxine (T4) and triiodothyronine (T3).
Thyroid scan - An image taken of the thyroid gland after radioactive iodine is taken by mouth.
Thyroidectomy - The surgical removal of part or all of the thyroid gland.
Thyroiditis - Inflammation of the thyroid gland. Can be caused by viral, autoimmune or other underlying medical
conditions.
Thyrotoxicosis - High levels of thyroid hormone.
Thyrotropin - A hormone produced by the pituitary gland.
Tinnitus - A sensation of noise (as a ringing, roaring or buzzing) that is caused by a physical issue and can only be
heard by the one affected by it.
Toxic multinodular goiter - Condition in which the thyroid gland contains multiple lumps (nodules) that are
overactive, produce excess thyroid hormones and thereby cause hyperthyroidism.
TPO - (Thyroid Peroxidase) This enzyme assists the chemical reaction that adds iodine to a protein called
thyroglobulin, a critical step in generating thyroid hormones. When there is a high detectable amount of TPO
antibodies, it can indicate Hashimoto’s where 95% of those test positive for the antibody.
Tremor - A trembling or shaking usually from physical weakness, emotional stress, or disease.
TRH - (Thyrotropin releasing hormone) Functions to stimulate the anterior pituitary gland to release TSH.
TSH - (Thyroid stimulating hormone) TSH stimulates the production and secretion of the metabolically active
thyroid hormones, T4 and T3.
TSI - (Thyroid Stimulating Immunoglobulin) The TSI level is abnormally high in persons with hyperthyroidism due
to Graves' disease. Autoantibodies to the thyroid stimulating hormone receptor are present in more than 90
percent of people with Graves disease.
Tumor - An abnormal growth. Tumors may be benign or malignant by cell type.
U.S. - (Ultrasound ) A procedure in which high-energy sound waves are bounced off internal organs and make
echoes. The echo patterns are shown on the screen of an ultrasound machine, forming a picture of the organs or
tissues.
Vitiligo - An autoimmune skin disorder caused by attack of the immune system on the pigment-producing cells
within the skin.
WBC - (White Blood Cells) Refers to a blood cell that does not contain haemoglobin. These cells are made by bone
marrow and help the body fight infection and other diseases.