New thyroid test fast, accurate

WASHINGTON, July 26 (UPI) -- The Georgetown University Medical Center in Washington has developed a fast and accurate way to measure a major hormone released by the thyroid gland.

Approximately 27 million Americans have thyroid glands that produce too little of the hormone, thyroxine, a condition known as hypothyroidism, or else the gland produces too much, known as hyperthyroidism.

Thyroxine regulates the body's metabolism, and hypothyroidism, associated with fatigue and weight gain, is much more common than hyperthyroidism, characterized by weight loss. More than eight out of 10 patients with thyroid disease are women.

To treat these conditions, physicians need to know how much synthetic thyroxine to either give patients or how much natural hormone should be blocked, and there have long been concerns that the common "immunoassay" test now in use worldwide is neither specific nor very accurate.

The study, published in the journal Thyroid, found the new test method was far superior to the immunoassay, and just as good as a very expensive, time-consuming, but very accurate laboratory analysis that is less commonly used.

"This is a very specific test and is not plagued by the false readings that make the currently used immunoassay test notoriously inaccurate," one of the study's investigators, Dr. Jacqueline Jonklaas, said in a statement.