Hello Dr Fox,
When my son was a toddler, he ate a piece of walnut bread. He immediately went bright red and fiddled around with his mouth before vomiting.
My husband and I both come from 'allergic' families (his older children have hayfever, asthma, eczema and a severe egg allergy; he and I both suffer from eczema; his father was severely allergic to all nuts).
Following the walnut episode, we duly trundled off to the GP, and were referred to the allergy clinic at our local hospital. When our appointment finally came round, some months later, he was given some blood tests which showed that he was allergic to grass pollen and was "possibly" allergic to nuts. The advice was to have him re-tested when he turned five.
He is now six, but nothing on earth could persuade him to repeat the blood test experience. The blood tests were, unfortunately, done in a rather ham-fisted manner (and had to be repeated as a result), and my son has still not forgotten the whole experience!
About six months ago, my husband gave our son a piece of banana cake with a nice juicy walnut on the top. After eating it, our son said that his mouth hurt; I suggested that he might have bitten the inside of his mouth, which he denied. A couple of minutes later, he went to the loo and suffered one bout of violent diarrhoea and vomiting. It may have been a pure coincidence, but he had no other symptoms of illness and within around three hours, he was pale but hungry!
This is all rather long-winded, but my questions are as follows:
Is there any way that he could be re-tested without the need for another blood-test?
How accurate are allergy tests?
Is it possible that my son could be allergic only to walnuts? (He has never tried any other kind of nut, but eats hazelnut-containing Nutella very cheerfully!)
If my son does have a nut allergy, should my four-year-old daughter be tested, too? To my knowledge, she has never eaten any kind of nut.
We would be happy to pay for tests if only we knew exactly what it was that we needed, and could be sure that the results would be reasonably accurate!
I would be very grateful indeed for any advice...