Posts Tagged ‘allergy’

Scratch Tests tell little...and tell a lot!!

Tuesday, May 17th, 2011

After 15 minutes this is the reaction from a small drop of tahini paste

So after 3 years of a Sesame allergy and numerous scratch tests, we had hope that our oldest son would grow out of his sesame allergy.  What makes sesame difficult is that the FDA does not recognize it as a top allergen and therefore most restaurants and some food manufacturers don't label or document it in ingredients.  It is also very hard to find bread that is made in a bakery without sesame. Our allergist, after a recent scratch test, decided to run the blood work to examine sesame further in my son since the results of the scratch test were inconclusive.  The blood work supported this uncertainty.  The only way to remove doubt about his allergy was a food challenge. This past Friday,  up at the crack of dawn, we went to the hospital with our allergist to test sesame.  The good news was that we didn't have to stay right through the full process because we never got started. For the food challenge w e brought with us Tahini paste that is pure sesame seeds crushed up. We were very nervous and didn't know what to expect.  Our allergist was very confident with the process and as an initial step, she took a sample of the paste and ran a scratch test.  To everyone's surprise,  the skin reaction to the scratch test was HUGE.  We had never seen HIVES jump from the original circle.  See the Image included.    At this point we stopped the process and never made it to the food challenge. What can we conclude from this experience... 1. The scratch test with the real food before the challenge was a wise decision on the part of our allergist. 2. The difference in scratch results when we looked at the allergen in its purest form, as compared to the Scratch tests done with fabricated or diluted samples makes me wonder why there is so much unknown about reactions.  Was it the purity of the allergen? Was it my son's immune system changes?  No one knows...ask your allergist and let us know their thoughts! Based on our experience,we will ask our allergist if bringing the purest form of the allergen when we are scratch testing is better than relying on the diluted samples they have had sitting in their offices for months? We continue to seek out answers to our allergies and it seems that the more we learn, the more questions and uncertainty is presented to us.   Thankfully our allergist has the right process and did not expose our son to sesame in a food challenge. Hope we can all learn from these experiences...please share your allergist experiences too! Steve Rosenbaum Father of 2 allergic boys (and one not allergic...go figure!) and Founder of AllerDine.com