Peanut Allergy - Skin prick test - 5mm - what does it mean?

[DeirdreB]

My DS (12 months) had a skin prick test last week and had a 5mm weal in response to peanut (and a 3mm response to sesame). We requested the tests after he had red itchy skin after sesame and vomiting and red itchy skin after peanuts. There is no history of peanut allergy in our families so this was not something we were expecting.

Anyway, I didn't ask nearly enough questions when I was there - What does this mean? Is a 5mm a "bad" result? Is a severe reaction likely or is vomiting / itchy red skin relieved by Piriton more likely? Should we ask for an epipen?

Thanks in advance for your help.

its means that your child is allergic.

however, it does not show/or predict severity of future reactions, because each reaction can differ.

it does mean that your child must not eat those foods, in any amount.

you do need to talk to gp/allergist about epi pens, as that might be the way forward, its not for everyone to say def yes.

a immunologist may prescribe them, or push for you to have them, or he/she may decide that because your child is so young you have more control over diet etc. they do tend to differ on this area in the uk. from what i hear from usa and canada its a matter of course to be prescribed epi pens.

but the real choice is yours, its a big comitment, and huge change of life style.
commitment to learning when to use, and how, and to remember to have it with child at all times. all future adults who have care of your child will have to be fully allergy aware and confidant to use the epi pen.

i do know other parents that have chosen not to have epi pens for their children, as they feel they can control the food they eat.
so far , that works for them.

in our case we pushed for epi pens , after immunologist said we didnt need them yet. however a month after appointment , we discovered more allergies, with differing levels of reaction.
we got epi pens from the gp , and when we returned to our imunologist, and he heard about the new allergies, he changed his mind and offered us some. thankfully we already had them.
our son was about 2 yrs old then, and we have had some close calls, and used the epi pen once, when he was 12yrs.
he is now 14.

so , on the one hand, its rarely needed, but its there for when we do need it.

A wheal of 8mm of more means it is extremely likely that a person will have a reaction when they eat nut. Below that level its less clear cut as many people with tests below 8mm do not have clinicaly significant symptoms. However as your child has vomiting and red skin after eating nuts they are likely to be one of the ones who will react. Therefore you should avoid peanuts and even "may contain" products.

The good news is that your child is very young and that they may outgrow this by age 5.

Asthmatic children need help quicker in an emergency. Therefore if your child shows signs of asthma (like night time cough) you need to have that investigated promptly and an epipen if asthma is confirmed.

If your child is not asthmatic its more debatable and some consultants refuse to prescribe. We were lucky and had a consultant who did. We didn't need to use the epipen until they were in secondary school but without it I think my (non-asthmatic) child would be dead by now. Most very young children will recover with piriton if given immediately, an ambulance should be called if there is any sign of breathing problem or going floppy.

Personally we pressed for an epipen but mny people manage without them.

Thank you for your responses. Very helpful. Will be watching everything very carefully. We go back again in six months so will talk about an epipen then. In the meantime he's with me every day so I can control his food intake. The peanut butter and tahini have already left the house!!

How do you manage things like food for your other children, mine like museli and oat bars that may contain traces of nuts. Do you just keep these seperate (we have put these in a separate cupboard for now) and be vigilant or do you keep all nuts / seeds out of the house? My other DC's are very allergy aware already but is it too much to take the risk?

having had to sit by my nut-allergic child twice while they struggled to breathe (and hence to live) I would not allow a nut in the house. The only "may contain" produce I permit is ice-cream and then only if I can't buy alternative products. We didn't have an epipen the first time and all you can do then is phone for help, sit, keep your child calm and pray help arrives in time. The epipen reversed the reaction in minutes.

Other people believe the non-allergic children shouldn't be "deprived" but if they deprived their sibling of life how would they live with themselves afterwards? They can eat such things outside the house provided they wash their face and hands well afterwards. Water alone doesn't remove nut traces, they need to use soap.

You can buy nut free muesli. We have lots of nature's pleasure as a local shop was selling it off. Kellogg's Nutrgrain bars have no nut warnings. There are others, I'm just telling you what's in our cupboard.

Without an epipen, though, I wouldn't run any risk.

If they didn't offer repeat testing you should arrange it when your child is going off to playgroups. A decreasing wheal size would mean you might ask for a food challenge, one over 8mm or any reaction meantime and you should ask about epipens.

We never had a nut in the house before sdd was desensitized and dd3 was tested. If we enter the washout phase of the trial with no nuts then the house will be cleared again.

Sdd1 grew up never having nuts and she is no worse off from the experience. If anything it taught her a level of compromise and tolerance. She was allowed peanut butter if she went to grandmas alone and other nut traces if out without sdd2 but ritually washed hands/face and cleaned teeth before coming back.

Did you use Johnson's baby oil etc when he was tiny, by any chance?

No. We had problems with creams etc - could have been a weleda product which I think had seed oils.

Reason for question? Link?

skin cream use believed to be related to nut allergy. Can't be bothered to find link, google it.

Anything with ARACHIS oil in it is peanut oil, that's its Latin name - use on young babies can trigger the allergy.