Measured dehydroepiandrosterone sulfate positively influences testosterone measurement in unextracted female serum: comparison of 2 immunoassays with testosterone measured by LC-MS.

摘要

Nonextraction testosterone im-munoassays 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 sul-fate (DHEAS) interferes in several testosterone immunoassays, including the Roche Testosterone immu-noassay (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.