Help me understand Allergy/Intolerance testing

[JMJ]

My son is 11 months old. He has had a number of allergy or allergy-like reactions with mucusy, green stools, sometimes a bit of blood, a red ring around his anus, and a serious diaper rash every time there is a flair-up, which includes every time he gets sick of any sort. While he was exclusively breastfed, I eliminated gluten, dairy, corn, and soy and reduced all grains significantly, and it's almost all better, mustardy yellow poop except for when he's sick, just a little bit of a ring around his anus every once in a while. I don't think I've got it all figured out, but I'm close.

And then last week happened. It could have been that he got some kind of stomach bug. I suppose it's potentially possible that he got his hands on a piece of ice melt salt, but my fear is that he reacted to the single bite of egg yolk that he ate for the first time on Wednesday. Wednesday evening, he was inconsolable. Wednesday night, he was up crying in the middle of the night multiple times. Thursday, he had a dozen bowel movements, starting yellow, then getting progressively green, mucusy, and more bloody than I have ever seen. Thursday night was another difficult night, even waking up to poop (green and blood-streaked) in the middle of the night. Friday, stools were still green and mucusy, but no more blood. He was fussy Friday evening, but he slept better. Saturday, his bowel movements moved from green to yellow as the day went on, and Sunday was almost normal.

I don't know that he's allergic or intolerant to eggs, but that was such a severe, scary reaction for such a tiny amount of egg yolk that I don't want to trial it again. Moreover, I eat over half a dozen eggs every day, and that's a pretty significant amount of my diet to be taking out if it's nothing. I've already lost as much weight as I would like after having him, plus a few lbs more. Additionally, he recently had a posterior tongue-tie clipped, and he had been previously falling off the growth curve. Right now, I'm working to increase my milk supply to help him gain extra weight. Oh, and I'm also tandem nursing him and my 3 year old. I can't just cut more foods and not get enough calories and nutrients without a really good reason.

The theory that I'm working with right now is that I have done some great work healing my gut with cutting out my intolerances, lots of probiotics and whole food nutrients, broth and more, and I am doing a much better job of breaking down the proteins in my food into their amino acids before I absorb them, so very little whole protein from the foods I'm eating is getting into my milk. I see slight flair-ups in him when my gut is slightly compromised, like when I eat more sugar or grains. Still, I think I'm eating something that he is not reacting well to, so every time my gut is breaking down those proteins less well, I start to see some negative changes in his stools. I'm guessing it's eggs, but maybe more than that.

I'm looking for information on allergy/intolerance testing. I've been reading. Am I understanding correctly that IgE is a test of a true allergy, a serious and immediate reaction to a food? IgG seems more confusing for testing intolerances. There's a lot of opinions, and if I'm understanding correctly, what it shows is that your body is recognizing that your gut is absorbing certain proteins whole, without first breaking them down into their amino acids, so you may or may not be reacting to them, but you could potentially react to them because they aren't supposed to be in your bloodstream whole in the first place. Are there any tests that show whether such foods are causing clinical or subclinical reactions? I'm feeling overwhelmed with shooting in the dark and cutting back more and more things in my diet while my son continues to suffer.

[sbgrace]

I am not at all convinced by the research I've seen on IgG testing. I just don't believe the technology is there to get a reliable and accurate result. A lot of people end up cutting out a lot of foods that they don't need to cut with those tests. I know some people believe in them. It's just that the studies don't suport their accuracy (at all) and I know people who have gotten huge lists of foods that really weren't issues. Even standard allergy testing, which does have scientific backing, has a 50% false positive rate! I would expect at least that with IgG. The problem is with standard testing allergists will only test what you believe is reactive and often will follow up with a food challenge to confirm if there is any question. They know there is a high chance of false positives. With IgG you get a list of, often, tons of foods to just cut from your diet. You really don't know which of them are false positives. All of them might be. I'm not a fan and in your case I'd hate to see you lose foods unnecessarily which I fear would happen.

That said, I do believe in non-IgE mediated intolerance and also GI only allergies. The best way to figure those out, in my experience, is with food diaries and/or food challenges. That's how I would approach this in your situation.

Another thought, though I hate to mention, is that you could be dealing with something like EOS disease. It might explain the GI issues and failure to thrive. Have you seen a GI and, if so, did they test for that?

He's old enough for IgE testing. I don't know that a GI only reaction would show up though. I'm sorry you're dealing with this--it sounds like you've had a really rough time already.