Please help me understand the results of dd's allergy appointment and test

[PrettyCandles]

Background:
6yo dd has chronic catarrh, related hearing problems, intermittent asthma-type coughing. She has had eczema on her face since she was under 12m, as well as other rashes that come and go on her body. She has problems with bladder control, and occasionally with bowel control. She has been having a lot of behavioural problems since the catarrh problems began. She's been on the minimum dose of various asthma medications for the past 18m, which make her cough and catarrh manageable.

It was suggested that I try her on a dairy-free diet, as she had had reflux as a baby and vomitted within minutes whenever she had cow's milk (though not cow's milk based formula).

DF diet cleared her eczema and rashes up completely, but had no effect on the other issues.

So, what happened at the appointment:
Dd tested negative for dairy, dustmites, grasses, by skinprick testing. The result, however, was ambiguous, as she did not react to the histamine control. They repeated the histamine, and eventually she showed a small reaction. Because of this they also took blood to test separately.

The dr said that her nasal passages do not look like allergic rhinitis. He also said that the eczema was not an allergic reaction, because it had not involved the skin folds or the area immediately around the lips.

His conclusion was that dd is almost certainly not allergic to anything and that her cararrh and hearing problems need to be investigated by ENT. Her asthma is probably just 'one of those things', a childhood asthma that can't be explained and that she may well outgrow.

What I don't understand:
How could she not react to histamine? Has this happened to anyone else? (Neither the dr nor the nurse in the allergy clinic had ever seen this happen before.)

If skin-prick testing is the gold-standard, what's the point in blood-testing? How and what do they test?

If dd has in the past had eczema and rashes that cleared up completely on a dairy-free diet, surely that indicates some sort of connection? What is this if not an allergy? I am concerned because 2yo ds2 also had reflux and could not tolerate cow's milk, and has facial eczema which cleared up on the DF diet. What is more, as soon as he or I have any amount of dairy (I'm still bfing him), the eczema flares up again.

Why did they test for such a limited range of allergens? OK, she's not had any obvious major reactions to anything, but if there are chronic problems, could they not be caused by something that she is exposed to all the time, so often that a reaction might not be noticed - as was the case with dairy and her eczema?

Thanks for getting to the bottom of this long post!

bump

I can't explain it to you but I can tell you that because the immune system is very complex and not well understood then allergies are likewise difficult to understand and the tools used to determine them (like skin prick tests) are very blunt instruments.

Combined skin/blood tests will usually pick up allergies but not always - our doctor always tells us that reactions trump test results. So if cutting out dairy has cleared your dd's eczema then I would say she was allergic to it (I had horrible eczema for years as a child, also tested negative to dairy with skin tests but following an exclusion diet dairy and citrus were cut out of my diet and the eczema was gone wihin weeks)

Anyway, if a df diet benefits your children then I should just go with it. Have you tried keeping a food diary? Will try to post more later but baby just woken - sorry.

probably your child has not an allergy but an intolerance. Allergies show up as IgE reactions but intolerances are rather more difficult to detect.

Haven't heard of a totally negative skin prick for histamine in anyone who wasn't on antihistamine at the time (and even then they may test postiive). Who did the test? I would be concerned that the test wasn't done properly the first time or their histamine extract was mislabled! Sometimes you get negative skin prick tests and positive blood tests, no test is perfect. With a negative histamine test you really need a blood test as it will be done elsewhere.

I'd guess you've seen a paediatrican as there are few allergists around. It is worth seeing one if you can possibly get an appointment, even if you have to travel 100 miles/wait 6 months. Or if you are anywhere near the Royal National ENT they are more aware than most of the link between milk and ENT problems.

Thanks for your answers (and thanks, PR, for bumping).

Dd wasn't on antihistamines, but is on Montelucast (Singulaire). They double-checked with the consultant, who was certain that Montelucast would not affect the result.

She was being seen in the Paediatric Allergy clinic at St Mary's in London, by a dr who was an adult allergy specialist moving over into paediatric allergy. He was forthright about his relative inexperience with paediatric allergy, and said that he had double-checked everything with the consultant while dd was having her tests, just in case he had missed something specific to children.

well that means the test should have been done properly at least. Singulaire isn't supposed to affect histamine levels, it works on something else.

It is possible to get negative skin tests and positive blood tests so I wouldn't totally rule out an allergy yet. The consultant really ought to be better informed about intolerances, though, and to have discussed with you the difference between allergy and intolerance. Unless the blood test is positive I think I'd ask to go to the Royal National ENT - maybe Dr Glennys Scadding - see this Channel 4 chat with her www.channel4.com/community/showcards/D/Dispatches_-_Asthma.html