I’m a little confused [about] when to do a further workup for celiac [disease]. Do tissue transglutaminase and alpha-gliadin both have to be elevated to do anti-endomysial immunoglobulins and refer to gastro? What about the mega and gamma-gliadin with elevated tTG-2?

This is a great question: “When do you do you a workup for celiac disease?” And my honest answer is, it sounds like, Gavin, you’re saying in the context of having already run Cyrex Array 3, I’m seeing the tissue transglutaminase 2 autoantibodies being elevated, and so that’s sort of a red flag. Is it worth doing testing for celiac? In that particular case, if I see an elevation of tTG or tissue transglutaminase 2 autoantibodies, I’m going to tell the patient, “Look, I really recommend you just follow a pretty strict gluten-free diet,” especially if I’m seeing any other markers coming back elevated. If somebody says, “I don’t know that I can stick with a gluten-free diet. How important is it, really?” Or they might even say, “I’d like to be able to include some gluten. Do I have celiac?” Or maybe they feel uncomfortable going to restaurants saying, “Oh, I need to be gluten-free” that’s when I tend to offer testing for celiac disease. If somebody tells me, “Look, I already see the autoantibodies on this Cyrex panel; this is enough for me to stop eating gluten,” then I don’t necessarily think that further testing is necessary. The big question is, “What do you get out of additional testing?” Anytime you do testing, I think the question is always going to be what are we going to do differently? And so, I think you can have a lot of flexibility in terms of when do I do the follow-up testing for celiac disease. You’re saying, “Well, if I have omega and gamma gliadin autoantibodies plus tTG-2, is that most suggestive of celiac disease?” Not necessarily, but if this patient has a genetic predisposition toward celiac, if they have anti-endomysial antibodies, are they going to do something differently? That’s how I would think about testing for celiac disease. Certainly, the tTG-2 is going to be a trigger. You know the antibodies that are going to tip you off to a question of celiac, and so I think the question you really want to ask is, what are we going to do differently if this patient has celiac? Is the patient going to be stricter about it, keep gluten out of the house, etc.? That’s how I would approach it. Then, you asked, like, when to refer to a gastroenterologist. I don’t always refer to a gastroenterologist. If somebody is going to be strictly gluten-free, I don’t think there is a need for endoscopy and biopsy because [those are] invasive procedure[s]. Again, how is it going to change your management after doing it? Hopefully, that makes sense in terms of how to think about when do I—and that’s just sort of the general framework for how I think about when it’s appropriate to run the test, always thinking about how this would change management.