Confused with contact hives...allergy or not?

[6strings1song]

I am hoping someone can help me understand what is going on with my son and his reaction to dairy and egg. I feel so confused and down/defeated/exhausted about the whole situation.

In a nutshell, DS is 8.5 months old. He first reacted to dairy (uncooked pure milk) when he was 5.5 months old. It was in a puree and he came out in contact hives wherever it had touched. This was on the 4th and 5th exposure to the puree. We immediately excluded dairy and after 2 weeks we tried a small splash of milk on his skin and hives appeared. Similar situation with scrambled egg, contact hives on 5th exposure. Consequently eliminated egg from diet.

Fast forward to 7 months, we went for a private paediatric allergy appointment and testing. All skin pricks (milk, egg, soy and peanut) were negative (good news right?) and we were instructed to try both the milk and dairy ladder as a way to reintroduce these foods. I understand that skin prick false negatives are rarer than false positives, but the allergist seemed quite confident that DS didn't have an IgE mediated allergy.

As instructed we have been progressing up milk ladder and finally reached the top, but the contact hives have returned. I had been replacing the oat milk in his breakfast cereal with real milk...tablespoon by tablespoon over 5 days. 5th day, contact hives. Appear within about 5-10 minutes and disappear in about 20 minutes. We tried again the following day with hot microwaved milk, same situation. He seems to be tolerating yoghurt and cheese etc. Going to eliminate pure milk again and just give the foods he can seemingly tolerate.

Does this mean we have resensitised him by doing the milk ladder and this is an IgE mediated allergy? Is this reaction some sort of weird contact urticaria? Or a skin based non-IgE allergy? Has anyone experienced anything similar?

We are now gingerly doing the egg ladder, but I expect the same situation to be honest i.e. initial tolerance but hives appearing as the days go on.

We have booked a follow up appointment with the allergist and will raise these questions then....but just wanted to gather some mumsnet knowledge (and solidarity) in the meantime. Thanks everyone.

That sounds difficult and I’m not surprised you’re fed up. I get occasional urticaria and never got to the bottom of what triggers it. It’s concerning when one’s lips swell up, as you inevitably worry about the throat, breathing etc.

When it happens I respond very well to a high dose of Piriton, so always have it handy.

I hope you get some answers soon.

Skin prick tests are unreliable in young children and clear reactions should be used to determine allergies ahead of negative skin prick tests. I have friends who's children's allergies didn't show up on skin pricks until aged 4.

I would go back to the step on the ladder that doesn't result in hives and contact your paediatrician/dietician

Hey, my 10month old has started reacting alot lately to foods he has been having since 6/7months old. First watermelon then kiwi. His torso is coming out in hives after eating them but nothing on his mouth. We have been told to introduce nuts and I gave him half a finger nail probably less of peanut butter and he came out in a rash on chest and belly and hives on torso too.

has anyones child reacted like this but they didnt turn out to be true allergies? Im thinking is it just the proteins his body isnt use to? We have been advised to hive a tablespoon 3 times a week of peanut butter so maybe I will get a better idea then but just thought I ask do anyones child just come out in hives but its not an allergy?