Why Men need to request the sensitive, LC/MS assay for serum E2 measurement

Why Men need to request the sensitive, LC/MS assay for serum E2 measurement

Why Men need to request the sensitive, LC/MS assay for serum E2 measurement

A real World Example of why Men on TRT or using AAS might need to request the sensitive, LC/MS assay for serum E2 measurement

LC/MS assay offer greater sensitivity and lesser interference by other steroids.

The commonly used estradiol test may overestimate estradiol.

That test uses immunoassay technology that might be cross reactive to other compounds and cannot differentiate C-Reactive Protein (involved in inflammation) from estradiol, so it reads the combination of the two as estradiol.

This sensitive estradiol test is based on liquid chromatography/mass spectrometry (LC/MS), an assay technology that does not have that limitation.

Look at the difference here on this client from the same Blood Draw, the Lab he used did not do LC/MS assay in-house and so hence different Labs here.. but same client, same single blood draw, same day


AAS use at the time of this Blood Draw

500mg Test Enthate Week
500mg Nandrolone Week
12.5mg Aromasin EOD

Victor Black

J Clin Endocrinol Metab (2013) 98 (6): E1097-E1102.

Immunoassay-based techniques, routinely used to measure serum estradiol (E2), are known to have reduced specificity, especially at lower concentrations, when compared with the gold standard technique of mass spectrometry (MS). Different measurement techniques may be responsible for the conflicting results of associations between serum E2 and clinical phenotypes in men.


Our objective was to compare immunoassay and MS measurements of E2 levels in men and evaluate associations with clinical phenotypes.

Design and Setting:

Middle-aged and older male subjects participating in the population-based Osteoporotic Fractures in Men (MrOS) Sweden study (n = 2599), MrOS US (n = 688), and the European Male Aging Study (n = 2908) were included.

Main Outcome Measures:

Immunoassay and MS measurements of serum E2 were compared and related to bone mineral density (BMD; measured by dual energy x-ray absorptiometry) and ankle-brachial index.


Within each cohort, serum E2 levels obtained by immunoassay and MS correlated moderately (Spearman rank correlation coefficient rS 0.53–0.76). Serum C-reactive protein (CRP) levels associated significantly (albeit to a low extent, rS = 0.29) with immunoassay E2 but not with MS E2 levels. Similar associations of immunoassay E2 and MS E2 were seen with lumbar spine and total hip BMD, independent of serum CRP. However, immunoassay E2, but not MS E2, associated inversely with ankle-brachial index, and this correlation was lost after adjustment for CRP.


Our findings suggest interference in the immunoassay E2 analyses, possibly by CRP or a CRP-associated factor. Although associations with BMD remain unaffected, this might imply for a reevaluation of previous association studies between immunoassay E2 levels and inflammation-related outcomes.

from J Clin Endocrinol Metab (2013) 98 (6): E1097-E1102.

Comparisons of Immunoassay and Mass


The interpretation of Bloodwork in Enhanced Athletes – Creatine Kinase

The Interpretation of Bloodwork in Enhanced Athletes – Creatine Kinase

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One of the great challenges that Enhanced Athletes have when working with Primary Health Care Providers is the lack of understanding of the differences in what we would consider “normal range” Biomarkers between Athletes and the General Public

Being ” enhanced” only widens that divide

Creatine Kinase is the most sensitive enzyme index of muscle damage. It is an intracellular enzyme with three main isoenzymes and is found mainly in skeletal and cardiac muscle.

Creatine Kinase is commonly measured in the general population to assess damage to cardiac muscle post Myocardial Infarction ( MI ), AKA Heart Attack for elevation in CK levels following MI , occurs when blood flow decreases or stops to a part of the heart causing damage to the heart muscle.

But as I say Creatine Kinase is also abundant in Skeletal Muscle Tissue.

I have had many clients GP’s over the years express concern over elevated CK Levels.. when in reality the readings seen in that clients Bloodwork are exactly what we would expect to see in an Athlete, even a Natural Athlete.

The upper reference limits for CK in male and female athletes.

The upper reference limits for CK in male and female athletes are twice those for male and female non-athletes.

Since athletes have higher values than non-athletes, comparing the values of athletes to the normal values established in non-athletes is pointless

Layman’s Takeway ?

Keeping it simple.. always ask your Dr opinion but make sure if he is cautioning you against this or that that he understands the difference between normal for ” Citizen Joe” and normal for ” The SuperNatural Man ” they are not always the same.. and here in the case of Creatine Kinase by a factor of 2 X

ie The upper reference limits for CK in male and female athletes are twice those for male and female non-athletes.
Add ” enhanced” to the mix and its reasonable to expect that divide to widen even further, why ?

Creatine Kinase in Enhanced Bodybuilders 

Here we see CK in 4 Enhanced Bodybuilders 

All four bodybuilders had last trained about 72 hours before the test exercise. Their markedly increased CK at the start of the test may therefore be due to the previous period of muscle trauma induced by exercise. This marked elevation of CK before exercise (median concentration nine times the upper limit of reference range) may be a direct effect of the anabolic steroids.
When they were not taking steroids, ie as Natural Bodybuilders their initial CK was only about one and a half times the upper limit of reference range.

Why are the Pre-Training Reading Elevated ?

The reason for the pre-exercise elevation in CK could be

1, The steroids may have affected the integrity of muscle cell membranes, and the stress of exercise may have exacerbated the loss of intracellular substances such as CK and AST.


2, The bodybuilders as a result of enhancement may be able to sustain a higher level of exercise which could cause greater muscle damage.

Victor Black

Do Steroids ( other than Testosterone ) show up as Testosterone in your Bloodwork ?

Do Steroids ( other than Testosterone ) show up as Testosterone in your Bloodwork ?

Its a question a lot of Novices will ask.. when trying to understand Bloodwork for the first time

Interestingly the typical Bro reply is “NO” !

However like so much of what we do, the correct answer is “maybe”.. it’s actually conditionally true.

Conditional on who you are ( sex specifically ), what drugs we are talking about and ” to what magnitude” we are talking about ( technical correctness ) and what immunoassay is being used by your particular Laboratory.

Yes there are some drugs that basically no crossreactivity at all they include oxymetholone, stanozolol, and turinabol.

and there are some that are actually plausible

” Anabolic steroids are well-represented among compounds cross-reacting with the Roche Elecsys Testosterone II immunoassay at a test concentration of 0.1 μg/mL (100 ng/mL)

Seven compounds boldenone, 19-norclostebol, dianabol, methyltestosterone, norethindrone, normethandrolone, and 11β-hydroxytestosterone produced cross-reactivity of 5 percent or greater.

Nine additional compounds produced cross-reactivity between 0.5 percent and 4.9 percent 

Using the cross-reactivity values, the apparent testosterone concentration that could be produced on the Roche Elecsys Testosterone II immunoassay was estimated for compounds based on published serum/plasma concentrations, if available.

There is limited published data on serum/plasma concentrations of some of the anabolic steroids, with generally more focus on measurement of these compounds in urine samples, usually for the purposes of detecting use as performance-enhancing drugs in competitive athletics.

Of the anabolic steroids for which serum/plasma concentrations are available, methyltestosterone appears to be the one most likely to impact testosterone immunoassay measurements in males.

Norethindrone and nandrolone could produce clinically significant impact on testosterone measurement in women, as may androstenedione in patients with 21-hydroxylase deficiency

All compounds on the Roche assay the demonstrated cross-reactivity had 2D similarities to testosterone ”


Victor Black

Why did I not get an eGFR result on my last bloodwork ?

Why did I not get an eGFR result on my last bloodwork ?

eGFR is short for estimated glomerular filtration rate. Your eGFR is a number based on your blood test for creatinine, a waste product in your blood. It tells how well your kidneys are working.

But its a calculated result

IE eGFR is estimated GFR calculated by the abbreviated MDRD equation : 186 x (Creatinine/88.4)-1.154 x (Age)-0.203 x (0.742 if female) x (1.210 if black).

with a creatinine level of 1.2 mg/dl at 51 years Old and White Male my eGFR is 68 ml/min/1.73m2

An eGFR below 60 mL/min/1.73m2 suggests that some kidney damage has occurred.

Here is an online calculator you can use for free


Or yes you can ” pay” the Lab to tell you this..

That is the reason, you work it out yourself.. or you can pay someone else to do that.. up to you.

If someone has an eGFR result that is “severely impaired” or very high BUN level I would recommend they go back and get a full Renal Function Panel

Electrolytes and anion gap
Urea/BUN and BUN/creatine ratio

If you have a slightly elevated BUN then I recommend you consider 4 gm of astragalus a day at least until your next Blood work panel


Victor Black