Presently, there are three testing approaches to evaluate thyroid function. The clinical validity and accuracy of each is briefly summarized below. 1. Total Hormone Measurements Total serum thyroid hormone measurements are usually not the best confirmation of clinically suspected thyroid disease. Total serum T3 and T4 measurements are poor indicators of thyroid-associated thermometabolism. More sensitive methods of diagnosis are needed. 2. Index Methods (T7) These are indirect measures i.e. Estimates of the free fractions of T3 and T4. The fT4 index is calculated by multiplying total T4 by T3 resin uptake. Most methods involving indirect estimates of the free fractions of T3 and T4 are susceptible to a wide range of modifiers that include drugs, illness, liver function and changes in equilibrium between bound and free hormones during transport of serum specimen among others. 3. Multiple Free Fraction Measurements To enhance clinical correlations to laboratory thyroid assessments, the new salivary panel (STPTM) includes: Direct measurement of fT3 Direct measurement of fT4 Direct measurement of TSH Thyroid Microsomal Antibody (TPO) The STP (trademark) is not an estimate or an indirect measurement of thyroid hormone levels, but is a direct reflection of tissue hormone concentrations. This panel is an economical tool which can enhance the diagnosis of clinical and subclinical thyroid problems. Thyroid Antibodies The salivary panel includes a measurement of the antibody level against thyroperoxidase (TPO); also known as anti-microsomal. TPO antibodies are positive in 10 percent of the adult U.s. population and have close correlation with thyroid dysfunction. Higher TPO antibody is more prevalent in women of all ages than men. Clinical studies have shown a close correlation between positive TPO findings and thyroid infiltration by lymphocytes, even in the face of normal thyroid function. Therefore, positive findings of TPO antibodies in clinically normal individuals usually indicate occult autoimmune thyroid disease. Major Signs of Thyroid Disease Hypothyroid Fatigue/Lethargy Dry skin/hair Cold Intolerance Constipation Facial Swelling Weight gain/loss Hemorrhagic Menstrual Irregularities Hyperthyroid Nervousness/Anxiety Palpitations/Arrhythmia Fatigue Insomnia Weight loss Increased appetite Bowel hyperactivity Increased sweating |