289) A 32 year old male athlete is evaluated in the office for bilateral breast enlargement. He is a state champion in running and is scheduled to participate in the national level running championship in few weeks. He is very concerned about his appearance. He denies using any illicit drugs or exogenous androgens or aromatase inhibitors is seen in the office during a routine follow up visit. His past medical history is unremarkable. Physical examination reveals gynecomastia bilaterally. His laboratory investigations reveal:
WBC 8.8k/µl
Hemoglobin 18.5 g/dL ( Normal = 13.0 to 16.5 gm%),
Mean cell volume (MCV) 84 fL
Platelet count 310k/µl
Which of the following is most useful in establishing the diagnosis?
A) Erythropoetin level
B) Urine Drug Screen
C) Serum Total Testosterone
D) Urine Testosterone/ Epitestosterone ratio
E) Serum Free Testosterone
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Archer USMLE Step 3 Blog 
C
b. hes on steroids.
D
b
D
•The method currently considered most accurate is determination of the ratio of carbon 13 (13C) to carbon 12 (12C) in urinary metabolites of testosterone using isotope ratio mass spectrometry
I am not sure but seems like “A”. his Hg is 18.5
b
All of those test are necesary to evaluate this pacient, but with the history of to be athlete and because is so easy, the anwser is: B. Urine drug screen
D…the question asks about the “most useful” in establishing the diagnosis
bbb
In every male body a certain ratio of the hormones testosterone to epitestosterone are produced on a daily basis. In a typical male, this ratio rarely goes over 4 parts testosterone to 1 part epitestosterone. Therefore, if an athlete were to inject exogenous testosterone into the body, testosterone levels would increase, but epitestosterone would not. This would dramatically changes the T:E ratio.
According to WADA if the ratio of testosterone to epitestosterone is greater than 4:1 (changed from 6:1 previously) it’s considered evidence of possible doping and leads to further tests … the key word is “further testing” This means it’s not finalized. . . a Carbon-Isotope Ratio test or CIRFloydLandis test is usually performed at this point. This is how Tour de France Champion Floyd Landis was caught.
WADA’s Code advices two different practices to determine if the increased T:E ratio is due to a physiological or pathological condition or to administration of exogenous hormones … However, there are documented cases of non-doping athletes with T:E ratios greater than 6:1 … In that case additional testing is required to determine the etiology of the elevated ratio
if an athlete’s urine test produces a ratio that is above 4:1 … at least three additional samples must be tested … These may be samples that were previously collected and analyzed or unannounced future tests … If the results are less than 30 percent for males and less than 60 percent for females … then it’s likely that the T:E ratio is naturally increased … thus declaring the athlete’s test as “Negative”.
WADA doesn’t consider genetic factors … However, in several cases natural testosterone is high (greater than 4:1 ratio)… as documented and recorded in the following races:
Hispanics 5.8:1
Caucasian 5.7:1
Africans 5.6:1
Depo-testosterone_200_mg_mlaAsians registered 3.8:1 in the tests after steroids were added to their urine samples … i.e. they have more room for tolerance.
An epitestosterone urine concentration greater than 200 ng/mL indicates its misuse (some people try to take additional epitestosterone to correct the balance … When officials detect this, a person is said to be “positive” for use of epitestosterone.
Testosterone to Epitestosterone was set at 6:1 by the IOC Medical Commission in 1982 as a final positive test … however it changed recently to 4:1.
*Carbon-Isotope Ratio test (CIR test) is a test that determines whether the extra amount of testosterone in the urine is endogenous (naturally produced) or exogenous (pharmaceutically taken).
The carbon isotope ratio is the ratio of two variants of carbon-carbon-13 to carbon-12 (these numbers indicate the atomic mass of the carbon which is the total number of protons and neutrons found in the nucleus). C-12, contains 6 protons and 6 neutrons, whereas, carbon13 contains 6 protons and 7 neutrons.
The measurement for pharmaceutical testosterone … which is synthesized from plant steroids, is different from natural testosterone because the molecular carbon framework is put together differently by plants and humans. Pharmaceutical testosterone contains less carbon-13 than endogenous testosterone.
http://www.rxmuscle.com/articles/chemical-enhancement/2325-understanding-the-testosterone-to-epitestosterone-ratio-drug-test.html
As you can see, the drug testing protocols are very scientifically specific and without a knowledge of this science, it becomes very easy to fail sports-specific drug tests.
Answer D