Comment by jerf | Hacker News Reader

Comment by jerf | Hacker News Reader

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Best medical research is a bit coy on this front; they keep trying to make lab tests and such, but what you'll find is that all the lab tests aren't definitive. Biopsies aren't definitive, and like I said, I've got personal local evidence to back this up, though you can find that tidbit everywhere. The blood serum tests aren't definitive as discussed in the last discussion, and overlap with other conditions even when it does show there. The genetic tests aren't definitive because they remain unsure exactly what causes it. (There are ideas, don't take that to mean there's no clue, but they aren't sure yet.)

What it comes down to is that the best way to find out is to just do it, but, well, as much as I love Western medicine in general it seems to be a bit hesitant to recommend that, they'd rather have a definitive procedure. (Me too, honestly, but if we can't, we can't.) So it's not like I can point to a peer-researched paper. It's just that if you dig into any given test, it's agreed not to be definitive, and the net practical result is that while the best research won't come out and say it, the best way to see if you have it is the trial.

And as CapitalistCartr says, the telltale sign is that you will be sick as a dog, probably well into the next day. I experienced headache (or migraine, if you prefer, bad headache), nausea, the feeling of my intestines pulsing, and general lethargy, but I don't know that that symptom list is "official". What I am sure about is that there will be no mystery left. We're not talking "moderate chance of loose stools", we're talking "don't make plans for the next day".

The tests for Celiac are extremely good. 95% sensitivity and specificity? My life would be amazing if we had that kind of accuracy for every disease.

The bigger problem is probably that people think they have Celiac when they actually have some other real problem that is not Celiac. Mislabeling things is deleterious for patient and physician alike. This is why, unless you actually have evidence to back up your claims about this test, you really should be much more cautious.

If you can point to controlled trials or published works that show that your test is sensitive and specific for -- or even associated with -- Celiac, I'm all ears.

However, I refuse to accept anecdote. Why not? I accept anecdote only in the absence of any evidence. We have actual evidence supporting actual tests that, while imperfect, have known error parameters. The fact that these tests are imperfect does not mean that your imperfect test is just as good; that's a logical fallacy.

Sure, if eating X makes you feel bad, don't eat X; nobody would disagree about that. But don't label it Celiac unless you can show that your home-grown test faithfully diagnoses Celiac and not something else.

"The tests for Celiac are extremely good. 95% sensitivity and specificity"

Well my bloodwork came "strongly positive", and the biopsy was negative. So what do we make of that?

Your first bloodwork was neither here nor there. Your second bloodwork was positive. At that point, you rightly earned a biopsy. The biopsy is the definitive diagnosis, unless you had been on a wheat-free diet prior to the biopsy (which would cause the duodenum to return to normal). That wasn't the case, right?

Now, the interpretation of the biopsy might not be great. Have you considered asking your GI to send it to (somewhere else of your choosing) to get a second opinion?

Edit For some reason, your other posts seemed to convey that your GI was not very confident in her biopsy of your duodenum. This does make me a bit nervous. This is why it's hard to play doctor over the internet. If we were in real life, I could probably get a much better sense of whether or not to trust the biopsy. Hopefully her biopsy is at least good enough to prove to an outside reader that she did indeed biopsy the duodenum...

I actually did go gluten-free for about 7 days prior to the biopsy (yeah, that was dumb). When I had my GI appointment, she had me go back on gluten for 3 weeks prior to the procedure, which I dutifully did.

She said I was extremely uncomfortable during the procedure, more so for the colonoscopy than the endoscopy/biopsy. I don't think she said outright that it prevented her from getting good samples, but she did say that it might make sense to repeat the procedure in a few months if the genetic test comes back positive, or if the gluten-free diet produces a positive result (of course with appropriate gluten-challenge beforehand). She said that if we do that she'd give me full anesthesia so that she can get further into the tract for samples.

I would certainly consider asking for another interpretation of the biopsy. Do they actually keep them around for that kind of thing? Where would I request it to be sent?

Thanks very much for your insight, carbocation.

Not dumb — in fact totally understandable — but yeah, that may confound interpretation of the test. Does your GI doc know this?

I'm not fully versed in the art of asking for another opinion, but I think it would be reasonable to get your doc involved. You could basically say that you appreciate the care she's given you and want to keep her as your GI doc (if true) but you'd also like to get another person to take a look at the biopsy sample, since it is obviously a very valuable and hard to get piece of tissue. I'm sure she could recommend another person to interpret the samples for you. I'm not positive that Celiac biopsy samples are kept, but I know that many other biopsy samples are, which is why I suspect that these are, too. At the very least, they should have images of the samples. Based on her apparent discomfort with the procedure, I'm half wondering if there was a misinterpretation, and I'm half wondering if she was unable to biopsy the right tissue; both of these concerns could be resolved by a third party. It wouldn't be cheap, but it has a small chance of saving you from having to do another biopsy.

That said, in the setting of a one week wheat deprivation diet, interpretation probably won't be totally clear even if you did have Celiac, so a second opinion on these samples may well not be worth it.

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