This ultrasensitive estradiol test is recommended for men. The commonly used estradiol test may overestimate estradiol in men. That test uses immunoassay technology that cannot differentiate C-Reactive Protein (involved in inflammation) from estradiol, so it reads the combination of the two as estradiol. This ultrasensitive estradiol test is based on liquid chromatography/mass spectrometry (LC/MS), an assay technology that does not have that limitation. 

Important note:  The blood sample is sent out to Quest Diagnostics Nichols Institute San Juan Capistrano, Caifornia.  Overnight delivery and testing is performed on Sunday and Friday.  Reports are available within 5-7 business days from the time the specimen is collected.

The determination of TPO antibody levels is the most sensitive test for detecting autoimmune thyroid disease (eg, Hashimoto's thyroiditis, idiopathic myxedema, and Graves disease) and detectable concentrations of anti-TPO antibodies are observed in most patients with these disorders. The highest TPO antibody levels are observed in patients suffering from Hashimoto thyroiditis. In this disease, the prevalence of TPO antibodies is about 90% of cases, confirming the autoimmune origin of the disease. These autoantibodies also frequently occur (60%–80%) in the course of Graves disease.