Specific Food Allergies => Peanut/Tree Nut Allergy => Topic started by: brownie on May 26, 2015, 04:19:25 PM
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Title: Interpreting peanut/treenut rast results
Post by: brownie on May 26, 2015, 04:19:25 PM
I posted on the main board about whether to challenge but maybe I should have asked for numbers specifically. I thought I had seen a scale on the board somewhere but can't locate it. I am confused and wondering if anyone has more information...
Where does a 0.59 rast for almond fall on the scale of anticipated seriousness / class? Well aware numbers don't necessarily predict, but is this a range to oral challenge traditionally? The old scale I have from LabCorp states this is still Class III which seems to disagree with our current doc, who says <0.35 is undetectable and "negative".
Brownie
Title: Re: Interpreting peanut/treenut rast results
Post by: spacecanada on May 26, 2015, 08:48:16 PM
The chart I had from my GP years ago (2002) is this:
ImmunoCAP RAST (units are kU/L) Class 0 = <0.35 (absent/undetectable) Class 1 = 0.35 - <0.7 Class 2 = 0.7 - <3.5 Class 3 = 3.5 - <17.5 Class 4 = 17.5 - <50 Class 5 = 50 - <100 Class 6 = 100+ (Multiple health sites have the same numbers.)
I remember reading and just looked up the values for 95% negative (unlikely allergic) and 95% positive (likely allergic) for different allergens. 95% negative chance of allergy level for all listed allergens on the list was 0.35 (pending reaction history). 95% positive chance of allergy levels were: Egg = 7, Peanut = 14, Milk = 15, Fish = 20, Soy = 65, Wheat = 80. So maybe the number for 95% positive for almonds is higher than the number you received on your test, which could be the reason they want to do the challenge?
Best of luck.
Title: Re: Interpreting peanut/treenut rast results
Post by: brownie on May 26, 2015, 08:55:22 PM
Thanks! These numbers sound more like what our current doc is reporting, which makes him a class I. Brownie