Skin test tomorrow

[MandCmama]

Ugh.  Just me again.  Bracing for another, sure to be disappointing, visit to the allergist tomorrow.
     C failed his baked egg challenge at the beginning of the month.  We go back tomorrow for a peanut skin test, as we have no idea whether or not C is allergic to peanuts and he begins pre K next week.
     Last year at some point I began asking how we would determine if C was allergic to peanut. If I remember correctly, the allergist told me to go ahead and try it at home. When she saw my reaction she offered an in office challenge.  I asked how this would help since he'd never been exposed before, and she stated in utero exposure was enough. Well, I certainly disagree with that as both boys were exposed to their known allergens in utero and then exposed again once prior to reacting. So to my way of thinking, an in office challenge would only prime C's immune system if he is allergic, yes?
     So this skin test.  If it's negative, that also tells me zilch, correct? Since he's not been exposed? 
     Only a positive will really give me any information...information I don't want.
Please point out the flaws in my thinking!

[twinturbo]

I think a lot of your decision tree on SPT, IOFC, letting one child eat a potent allergen the other is anaphylactic to will depend much on whether or not you are asking for any accommodations from the school.

[MandCmama]

Well...being able to warn them would be nice...If I'm even able to figure out if the answers mean anything.  And I absolutely would feed him peanut.  His brother goes on egg dates with Mommy. Not a fan of peanut things, but anything to make my little guy feel special ;0)

[twinturbo]

We had the Uknow test done for my younger child who has no known exposure to peanut. All reactions system and/or anaphylactic have been to other allergen. But considering how potent an allergen peanut is, like you, we wanted to have as much data as possible.

All Ara were close to negative but not zero. Both Phadia and the allergist at the time read
the results as valid because the base value was not zero, indicating he had somehow become environmentally exposed to peanut. How, I'm not sure because nuts are the one allergen we don't live with in our home in any form. He certainly had no in utero exposure as I did not consume peanut during my pregnancy.

Thus on paper he is negative to peanut. But as we discussed with our current allergist it's inadvisable for two reasons. If that value is a false negative given his history of anaphylaxis multiple times each from a newly discovered allergen it could go spectaularly bad to say the least. He also knows it would be impossible to introduce peanut on the younger child who will most likely spread it through the house. Given older child's history of contact-to-ingestion anaphylaxis from other children he knows of no way to realistically manage contamination.

Having had an incredibly bad failure at our milk challenge which had the same potency and anaphylactic bells and whistles as peanut did for our older child, I say this: I am lucky I found out how bad it got from how little was ingested under the eye of a trained clinician from National Jewish than an accidental ingestion at home or at preschool where I or he would not have been around to deal with. I now have a clinical report of the event independent of my reporting.

[MandCmama]

Well, I neednt have worried. Blatantly positive.