My feed

to access all these features

Mumsnet doesn't verify the qualifications of users. If you have medical concerns, please consult a healthcare professional.

Allergies and intolerances

What are the benefits of RAST tests v Skin prick tests?

4 replies

Whelk · 17/11/2011 19:21

dd1 (4.10) allergic to egg, dd2 (2.7) allergic to milk and egg.
We are under a specialist but have only ever had skin prick tests.

From reading lots of the posts on this board it sounds as though others have had blood tests too.
What is the value of them? should I push for them?

OP posts:
Clara35 · 17/11/2011 21:31

Dont know much about this but doctor my ds goes to said they look at both skin & blood however they did skin prick test 1st yesterday & if results of that weren't any different to last year they weren't going to put him through blood test. They have done both tests at all previous appointments. I did ask yesterday if you can have a skin reaction ie if touched by in ds case milk & egg but be ok eating something & doctor said yes. Hope someone with more experience comes along to answer.

eragon · 17/11/2011 22:43

the ideal is both, esp at the start of diagnosis, skin prick tests are cheaper than blood tests and give instant , visable results, blood tests take 2 weeks for results.

for older teens seeing the hives from skin prick tests is a very visable reminder, if they havent had a reaction for years.

in the case of peanut, skin prick tests are very accurate. however , reaction status varyies considerably with each exposure. consided unpredicatable in reagard to reaction status.

both can give false positive and negatives, which is why doctors take reaction history in to account.

we have had blood tests at the start, and now for some years have had skin prick tests. after lowering skin prick tests or negative ones, we have had the chance to consider food challenges.

extreme side effects to skin prick tests are very rare, and considered safe for vast majority. a very small few have had more of a problem with them , but on the whole are very safe.

Whelk · 18/11/2011 18:33

Thanks both for your replies. I guess I struggle with not knowing how bad the allergies are although I guess the hive size gives an indication.
And I certainly don't want a reaction to happen!!

OP posts:
freefrommum · 18/11/2011 18:39

DS has had both although the blood tests were only more recently. Both types of test only give an indication of the level of allergy though and neither can predict how severe a reaction might be unfortunately. Consultant told us that he's known people with fairly low RAST results to have severe anaphylactic reactions and others with RAST levels off the scale (like DS) who only come out in hives. Food challenges are the only real way of testing whether or not an allergy has been outgrown (but also how severe a reaction could be in our case!).

Please create an account

To comment on this thread you need to create a Mumsnet account.