RAST test for intolerances?

[Laura032004]

I think there is probably a similar thread somewhere, but I can't find it, so sorry if this has already been asked.

DS is having RAST tests for gluten, dairy and soya on Monday. Any thoughts on whether I should give him these items before the tests? I've read both yes and no.

Also, are they unlikely to come up positive unless it is a proper allergy? He has stomach pains, diahorrea and sickness with gluten and dairy, and bad diahorrea with soya. He does get some excema patches after a while with dairy, but these are a week or so later.

Would any test show up a result for an intolerance? I don't think a hospital challenge would help, as they aren't allergy type reactions, just me knowing that he isn't himself IYKWIM.

I was told by a dietician (that we saw as a one off to work out what ds could eat whilst admitted to hosp for a chest infection) that we should be getting a lot of basic items (flour, bread etc.) on prescription. Do you have to have a positive result on some tests before they will start issuing prescriptions? It seems a bit of a postcode lottery as this dietician said (we were in hosp in Lancashire, but live in Cornwall!) that we would have been referred and seen v.quickly in that area, whereas here it's taken over a year to get anywhere.

Thanks

bump

hi laura, my ds has had rast tests for gluten, dairy, nuts, they all came back negative but his paed told me to stick to the diet hes on. he also suffers bad stomach pains and diarrohea. hes been awful this week and i put it down to the dairy/soya free marg i gave him and a tomatoe!ive read a lot on these threads about the RASTS being 100% positive but also that they are not. i also thought they had to have the bad foods in them to show positive, when tested my ds hadnt had dairy, soya, gluten for 10months so dont know if this is why he was negative but he obviously does have intolerances to lots of foods. there was a good thread on here the other day and the mums said that we know best and the dox arent much help with allergies/intolerances so i think a lot of the mums sort it out by eliminating foods themselves. not much help im afraid.good luck.xx

DS has had several tests, including RAST, for intolerances and allergies. In an ELISA test DS had a high score of intolerance to glutten, but was OK in the rast and the coeliac disease test, but we have notice that if he had a lot of glutten (said pasta several times a week) he develops diahorrea). He got a very high score for soya, egg and milk in a RAST test. I was not particularly suspicious of egg and milk but we have only realised about the extent of these allergies once that we removed the items from his diet. But still I'm still dubious about the results (his score for egg was unbelievable high but I have not noticed a great deal of difference since we removed it from his diet, and many times I wonder if we are stressing ourselves out for something that really is not having a lot of impact on him)

I really don't know what to ansewer to your original question, DS had the suspected offending items in the week before the test just becuase they were part of his regular diet. I don't think the result was affected as he was cleared for some items and confirmed for anothers

Thanks for those reponses Chandra and 7777777

RAST tests IgE, I believe, and intolerances don't usually involve IgE. however if you're being seen at Plymouth that's a proper allergy centre and they should be able to recognise an intolerance when they hear about it. Think there is a blood test for gluten but its not a rast test - sorry have to dash, can't check anything.

We're being seen at Truro rather than Plymouth Tatt. Is it Derriford Hospital in Plymouth that is supposed to be good? Might try and see if we can get referred across there if we don't have any joy then.

Bit more time now. You may see the same doctor at Truro. This letter talks about allergy services at the two places.
64.233.183.104/search?q=cache:boVmYBljkXoJ:www.publications.parliament.uk/pa/cm200304/cmselect/cmhealth/696/696we33.htm+allergy+clinic+truro&hl=en

Don't know anything about the man except that he's a proper allergy consulatnt so ought to be good.

Hopefully even if you see the paediatrician he'll have been properly trained because it sound as though the consultant allergist has some responsibility for the service there.

This is a bit about the blood test for gluten problems, you do need to have eaten gluten before the test but I'm sorry I don't know how far before is OK. With exclusion diets you normally have to leave 4 days at least between foods so if he's had gluten in the last 4 days that might be enough.

"Several different types of antibodies are associated with coeliac disease but the most specific is called 'anti-endomysial' antibody. If this is present in the blood, then you are very likely to have coeliac disease."

there is a breath test for lactose intolerance but they seem reluctant to use it, I suspect its unreliable. For prescribing I guess you'll need a consultant to say you have a problem. Have to go - impatient child demanding internet access

The RAST test DS had covered IgG antibodies while the ELISA test for intolerances reviewed IgE ones. Not sure if this is the norm.

Well, we had them done. Went quite well with the magic cream Just waiting for the results now - we might get them by letter, or we might have to wait until the next appt at the hospital.

how do you think it went - did you get a chance to ask questions/ get any opinion from them before the results? Dairy/soy intolerances probably won't show up on the test, gluten might.

Believe me Tatt, they will, if there's a problem DS's RAST results for dairy and soya don't leave any chance for a misunderstanding.

May not. My DS was def dairy intolerant and it did not show up on test.

We didn't actually see anybody to ask questions of - it was just a couple of nurses doing the bloods who didn't actually know anything about the tests.

I'm resigning myself to the fact that they won't show anything (so I don't get upset on the day IYKWIM). I do worry sometimes that I am denying him a lot of food unneccessarily, but then he has something by accident, and goes back to the way he was, which reminds me how bad things used to be.

We've got an appt to see a dietician in Apr, so if we get negative results, hopefully they might be able to help us with a proper elimination diet to get to the bottom of everything, as I am fairly certain there is still something else bothering him.

I'll be back with an update in a couple of weeks

sorry chandra but they don't - have family experience to confirm it. An IgE moderated allergy will show up but if the problem is an intolerance it won't necessarily do. We've had both positive and negative tests for different family members. There are other tests than RAST and they tend not to be very explicit about what it is you are getting. Unfortunately the tests are less successful where the problems are related to digestion problems.

This is my favourite link about allergy tests

www.allergy-clinic.co.uk/food_allergy_testing.htm