RF15 | PMON304 Utilizing LC-MS/MS for the clinical quantitation of testosterone using dried blood spot and how it compare to serum
Authors: Hauck Zane Z , Zava David T 
Published: November 2022

Abstract

Introduction
Hormones are the chemical messengers of your body. Steroid hormones like testosterone are a specific class of hormone that are produced predominantly in the gonads (sex steroids) and less so in the adrenal glands (corticosteroids). When too little or too much of testosterone is produced, adverse symptoms and conditions can occur. In order to restore the vital balance of hormones, detailed and accurate measurement of hormones is needed. Serum currently represents the gold standard when it comes to hormone testing. However, there are other body fluids such as saliva, urine, and capillary blood (finger prick) where the hormone levels correlate well with serum. A significant advantage of these alternative fluids is that they are non-invasive, or semi-invasive, can be collected "on the go" by the patient at home, and don't have the strict requirements for cold-chain shipping.

Objectives
The primary objective of this work is to show that finger-prick dried blood spot blood is quantitatively equivalent to serum when compared by LC-MS/MS testing in patients only producing endogenous testosterone. We will also show that topically delivered testosterone increases in a dose-dependent fashion, whereas serum levels of testosterone increase very little regardless of topical testosterone dosing.

Methods
Serum samples were collected by a physician and sent into the lab and analyzed for testosterone on a Siemens Immulite 2000 autoanalyzer. Dried blood spots were collected by the patient and sent into the lab and analyzed on an AB Sciex 5500 triple quadrupole mass spectrometer.

Results
Patients who don't supplement with topical testosterone show a strong correlation between endogenous venipuncture serum and DBS testosterone levels. In sharp contrast, samples from topical testosterone users show remarkably different results with hormone levels 10-100×higher in the DBS than serum results.

Conclusion
These results are significant because it gives a glimpse into which forms of testing are most appropriate for different patients based on the mode of steroid hormone delivery. Without using the proper body fluid for testosterone detection, patients potentially could be overdosed if serum results are used to guide therapeutic dosing. Also, venipuncture serum will fail to show "sports-doping" with exogenous testosterone, which easily can be identified with capillary finger stick blood. This is also significant as the World Anti-doping Agency has finally begun accepting these data as fact and have listed dried blood spot as an appropriate form of collection and analysis for drug testing. This can help find athletes using performance enhancers that would normally have skirted by the system (1).
WADA. (2021, May 21) WADA Executive Committee approves Technical Document for innovative dried blood spot testing method. https://www.wada-ama.org/en/media/news/wada-executive-committee-approves-technical-document-for-innovative-dried-blood-spot.
Presentation: Sunday, June 12, 2022 12:36 p.m. - 12:41 p.m., Monday, June 13, 2022 12:30 p.m. - 2:30 p.m.