Measured Dehydroepiandrosterone Sulfate Positively Influences Testosterone Measurement in Unextracted Female Serum: Comparison of 2 Immunoassays with Testosterone Measured by LC-MS

摘要

To the Editor:Nonextraction testosterone immunoassays of samples from women are nonspecific because of interference by closely related steroids (1). The reference method, isotope-dilution GC-MS is not suitable for routine use. LC-MS is increasingly being used with women because of its enhanced specificity (2). Not all routine laboratories have access to LC-MS.Dehydroepiandrosterone sulfate (DHEAS) interferes in several testosterone immunoassays, including the Roche Testosterone immunoassay (3). Roche claims that their Testosterone II immunoassay improves testosterone measurement in women, with reduced DHEAS interference. Some characteristics of this assay have been published (4). The claim that this assay is prone to less DHEAS interference has not been independently verified. We investigated the influence of measured DHEAS in the Roche Testosterone and Testosterone II immunoassays by comparing results obtained with LC-MS.Serum samples obtained from 184 consecutive women (22–41 years of age) participating in an in vitro fertilization program were stored at ?80 °C. None was taking any steroid-containing medication. Body mass index values were 19 kg/m2 and 30 kg/m2. Serum testosterone was measured with the Roche Testosterone and Testosterone II …