For Care Providers

Thyroid Panel

A NEW PERSPECTIVE IN THYROID TEST
Complete Thyroid Panel at a Reasonable Price
(includes rT3, T3, T3/rT3 ratio, T4, and TSH)

Meridian Valley Laboratory, Inc. (MVL) is offering an accurate radioimmunoassay thyroid panel. Included in the panel are reverse T3 and T3/rT3 ratio, in addition to T3, T4 and TSH values. The reasonably priced thyroid dysfunction.

In some patients, the characteristic symptoms of decreased thyroid function often occur after an identifiable stress, and persist even after the stress has passed₁. A myriad of debilitating symptoms can frequently be traced to a single source, "low T3 syndrome" with reciprocal changes in the circulation of T3 (which decreases) and rT3 (which increases). The biological effects resulting from these changes are at present not completely understood, but are potentially important in the body's adjustment to stress₂.

Wilson's Syndrome:
Our thyroid panel is based on the investigative work by E. Denis Wilson, M.D. ("Wilson's Syndrome" - also known as Multiple Enzyme Dysfunction or MED). Dr. Wilson reports that when a body is under stress (illness, fasting, cortisol), T4 (thyroxin) is deiodinized to Reverse T3 instead of T3 (triiodothyronine). As the T3 hormone levels in the blood drop to low levels, the patient's body temperature can subsequently drop below normal. When the body temperature decreases so does the function of important enzymes. Both the thyroid blood test and the body temperature test may be correlated to clinical symptoms of hypothyroidism.

About Reverse T3:
Reverse triiodothyronine (rT3) is a thyroid hormone produced primarily from monodeiodiation of the inner ring of thyroxin. Approximately 85% of T3 synthesis and nearly all of rT3 production may be attributed to the deiodination of T4 in the periheral tissue rather than by direct secretion by the thyroid gland. Physical, mental and environmental stresses can inhibit the deiodinating enzyme, 5' - deiodinase, causing less T4 to be converted to T3, thus decreasing the amount of active thyroid hormone available to the cells. More T3 is then shunted towards rT3 causing an elevation in rT3. Once identified, there are several alternative approaches to treatment. Meridian Valley Labsoratory, Inc. offers support for clinicians in provision of reference documents.

Specimen Requirements:
Serum: Draw blood in a Serum Separator Tube (SST) and allow to clot for 20 minutes, then centrifuge for at least 10 minutes. Pour serum to transfer tube; minimum of 3.0 ml serum is required. Freeze and ship via Overnight Mail in prepaid kit, Monday through Thursday delivery only.

Reference:
1. Wilson, E.D., Wilson's Syndrome, The Miracle of Feeling Well, 1996, p.3.
2. McCormack, P.D., MD, Ph.D., et al, Increase in rT3 Serum Levels Observed During Extended Alaskan Field Operations of Naval Personnel, Alaska Medicine, Jul/Aug/Sept 1996 p. 89-97.
3. DeGroot, Leslie J, et al, The Thyroid and its Diseases, Churchill Livingstone, Inc., 1996.
4. Goichot, B., et al Thyroid hormone status and nutrient intake in the free-living elderly, Interest of reverse triiodothyronine assessment, European Journal of Endocrinology 1994, 130:224-52.
5. Cheng, L.Y., et al, Film Autoradiography Identifies Unique Features of (1125) 3,3', 5' - (Reverse) Triiodothyronine Transport From Blood to Brain, Journal of Neurophysiology, Vol. 72, No. 1, July 1994.

ADDITIONAL INFORMATION
Pre/Post Adrenal Stimulation	Adrenal	Thyroid Panel	Serum DHEA
Methods for the Determination of Steroid Hormones