T Nation

E2 Testing Immunoassay vs LC/MS


#1

I read where the Immunoassay was recommended or the Quest 4021 method over the Ultrasensitive 30289 in the Stickies. However, I found this comparison where it says that the Immunoassay test is recording higher E2 values due to CRP (C reactive Protein). Which may imply the overuse of AI. Interesting topic.


#2

Indeed an interesting topic. And something I’ve run into lately.

If you look at the scatter plot at that link, those of us with super-high immunoassay results are outliers. Probably most people don’t need to worry too much.

My understanding is, there are three techniques for measuring estradiol: RIA, ECLIA, and LC-MS (radioimmunoassay, electrochemiluminescence immunoassay, liquid chromatography–mass spectrometry).

It’s well-known that tren inflates ECLIA results (in fact, apparently some guys use it to see if their stuff’s legit).

Personally, I’ve been relying on ECLIA from Labcorp. But since I started taking clomid, my levels have skyrocketed to over 150. The same week I had Quest 4321 done, which I believe is RIA. This reported a level well within range, in the 20s.

I can find no evidence or anecdotes about clomid affecting ECLIA.

So seems like I oughta be a case study. Trying to google this stuff basically just brings up case studies. Here’s one.

And another link.

I’m waiting on LC-MS and CRP results, and considering testing immunoglobulins.