New Peanut Allergy Query

[GreenShadow]

DS (in his 20s and living at home) recently had an anaphylactic reaction to peanuts when out in a pub.
A subsequent skin prick test confirmed this.
They also took a blood sample to send off and this has now come back negative and apparently didn't show any allergy!

Is this common? Anyone have any explanation for it?

Thank you.

My nephew-in his late 20's after a lifetime of peanut eating had an awful reaction.

And DD was about 22 when she went for allergy testing (due to some severe tree nut allergies) in order to get an epi-pen. Despite loving peanut butter and never having a problem she scored a horrifically high anaphylactic score for peanuts. The Dr said to immediately cut them out as it was only a matter of time until she had a reaction.

I just think it doesn't happen every time but can get worse. No idea why the skin test didn't show anything-could it have been something else?
I don't think I'd risk it