The skin prick test used for screening is not that reliable, she says. (sciencenews.org)
A few days after this close call an allergy specialist gave Ian a skin - prick test using an extract from the leftovers of the (cheese - free) pizza he had eaten. (newscientist.com)
Interestingly, based on the first case study, it is still possible to be allergic even though the skin prick test comes back negative. (wellnessmama.com)