Dr. Amy Nett: A hypersensitivity reaction more often refers to an IgE type of reaction. With hypersensitivity, what you think of is that normal immune response. You’ve had presensitization and you have an allergy to that, so I tend to think of hypersensitivity more as IgE unless you’re thinking delayed-type hypersensitivity, and that’s going to be a little bit modulated more by the T cells specifically. The next time I talk to Cyrex, I can see what’s meant by that, but I would suspect they’re talking more about an actual allergy.
Then you said, “Would you consider doing Array 10 to see if the patient is producing antibodies to white and yolk?” Well, that’s a little bit tricky because that’s about a $500 test, and if your only question is if they’re producing antibodies to egg white or to egg yolk, I don’t really think it’s worth the $500. If they’re not having a significant reaction that they feel uncomfortable with, then what you can do is have them take out eggs for maybe two to three months and then reintroduce the yolk first and then the white. Of course, it’s hard to really introduce just the yolk without the egg white. You almost always get a little bit of egg white, but you can start with mostly the yolk and see how that goes. So take them out for about two to three months. Then try reintroduction of the yolk. Two weeks later, try reintroduction of the egg white. I would do that over the $500 for Array 10.
That said, she produced antibodies, you said, to several foods on Array 4, so if that’s the case, depending on what her symptoms are, you might want to see if there are additional food sensitivities and things that she should remove from her diet. So the reason to do Array 10 would be, depending on her symptoms, if you’re concerned that more foods are triggering her.