skin test vs blood test

[basilsmom]

Can someone please explain how a skin test can come up positive and when tested for the same thing in the blood work it comes back negative. My ds skin test was positive for sesame seeds and tree nuts. I got the blood work yesterday and it was negative. I called the allergist but he hasnt called back yet. Thank you for any help you can give me.

[wendy1221]

My ped said the blood test is very inaccurate in young kids--there are LOTS of false negatives w/ it. The real test is does she react?

[basilsmom]

Wendy, Thank you, You are right. He does react.Sometimes its hard not to get caught up with all these tests. So much different information.

[Electra375]

I'll second -- a reaction to skin testing would out way a negative blood test. The blood test are noted for false negatives, as are the skin test -- it isn't a perfect science at all.
And most of all a reaction w/ or w/o a firm test result is still an allergic reaction and should be taken seriously at least by the parents.
My ds2 had a skin reaction all over his body to playing w/ 1" square of Rye Bread at Sunday School w/in 20 minutes. The blood test came back negative from the Pedi and the stupid pedi allergist failed to tell me he could not do a Rye skin test b/c he didn't have the extract for it!!! This was even after I called to verify they could do it : And after they had already done the other skin test -- like there is no way my kids would set foot in here to be poked again, idiots...
Okay sorry for the rant...