Evaluation of Testosterone/Epitestosterone Ratio Influential Factors as Determined in Doping Analysis

Abstract

The ratio of the concentration of testosterone glucuronide to the concentration of epitestosterone glucuronide (T/E ratio) as determined in urine is the most frequently used method to prove testosterone abuse by athletes. A T/E ratio higher than 6 has been considered as proof of abuse in the past; however, cases of naturally occurring higher T/E ratios have been described. Since the introduction of the T/E ratio in doping analysis, the parameters that may or may not influence the T/E ratio, possibly leading to false-positive results, have been debated. To achieve more insight on the influencing circumstances, an overview is given to obtain an objective view on the merits of the urinary T/E ratio. Relevant analytical aspects of the T/E ratio, potential parameters of endogenous and exogenous origins, as well as some alternative methods to determine testosterone abuse, such as the urinary testosterone/luteinizing hormone ratio, gas chromatography-combustion-isotope-ratio mass spectrometry, hair analysis, and high-performance liquid chromatography-mass spectrometry, are discussed.

Quantification of testosterone and epitestosterone in human urine samples by stir bar sorptive extraction – thermal desorption – gas chromatography/mass spectrometry: Application to HIV‐positive urine samples

“…The T/ET ratio is widely used as an antidoping control measure, but it has found relatively few applications in the clinical setting. Furthermore, very little scientific information is available regarding the excretion of T and ET during hypogonadism [49]. In one study by Hubl et al [50], it was shown that patients with hypogonadism excreted submolar amounts of both T and ET.…”

The Urinary Ratio of Testosterone to Epitetosterone: A Good Marker of Illegal Treatment also in Cattle?

“…E is of great interest in the field of human doping control because it is the denominator in the T/E ratio, an indirect marker of T administration. When T is administered to man, the excretion rate of urinary T increases, the excretion rate of E decreases and the T/E ratio increases (Van der Kerkhof et al, 2000). An increased T/E ratio is also an indirect marker of androstenedione and dehydroepiandrosterone administration.…”

Determinação de esteróides androgênicos anabólicos em urina por cromatografia gasosa acoplada à espectrometria de massas

“…No caso da testosterona, o limite tem por base a relação de concentração de testosterona/epitestosterona (T/ E) na urina. Um valor de T/E maior que 6 sugere o uso de testosterona pelo atleta (Van de Kerkhof et al, 2000). Desta forma, para essas substâncias, foi necessário fazer análise quantitativa.…”

“…No início da década de 80, a cromatografia gasosa acoplada à espectrometria de massas (CG-EM) surge como a técnica analítica de escolha para a detecção e quantificação de EAA em programas de controle da dopagem no esporte. Também, em 1983, foi estabelecida a razão Testosterona/Epitestosterona urinária maior que 6 (T/E > 6) para a constatação do uso de ésteres de testosterona por atletas e esportistas (Van de Kerkhof et al, 2000).…”