This may give  you a place to start your research.
We didn't elect to do any official testing.  There was enough of a genetic history in our family along with our daughter hitting almost every symptom of gluten intolerance in children that it was a diet change only.  Of course we monitor some things closely with our family doctor but have not urged us to do any testing because of the results we've had with diet change.
It is my understanding that the RAST does not pick up gluten intolerance or hypersensitivity.  Because the body does not have an allergic reaction to gluten but more so an inability to process the proteins properly.
Testing for celiac can be a blood test or a biopsy.  
This might help out with understanding the tests.  For us, we've chosen to not go with either because the testing requires the patient to be on a gluten containing diet and it is not something we are willing to allow Bird to endure or for us to have to deal with the situations that come up while she is eating gluten containing foods.
		
 
		
	 
Weeelllll, they already did biopsies when they went in for the colonoscopy, but I don't know if they were looking for Celiac's or not, I just assumed they wanted to look for things like cancer:o..........all tests came back "normal" ........I should ask at our appointment, though, obviously depending on the RAST results.  
What are some symptoms your girl has with gluten/wheat?  
I am really trying to be calm about the bleeding, the doctors keep on and on and on saying "he's fine, he's normal, it's really not a lot of blood, his blood counts are normal", etc.
But when your kid has blood dripping out of him on every bowel movement, and you know that it's not a fissure or hemmerhoids, it's quite worrisome

.  
We've had a break for a couple of months (once or twice a little bit), but now it's back every day, the same as it was before the colonoscopy.  He's not in pain or acting wierd, but it's not right.  I don't care what doctors think is "a lot" of blood, it sure is "a lot" to me.  One dr. at the ER asked me if it was 1/4 cup or more, and I did this 

 to him and said "if that was the case, I would imagine it would be considered a hemorrhage, right?  (which obviously wasn't happening)  To me, 1 tsp of dripping blood during a bowel movement (plus what's already mixed in the stool)  every day is a lot!  You say "a lot" to a doc, and they look at you with that stupid skeptical "yeah, right, you're an over-reacting parent" look.  Don't you hate that look???!!  It's really hard to just sit and wait and wait and wait for tests to be done, results, opinions, etc.  Blah.
I am feeling he's GOT to have some sort of food allergy/intolerance, because when he had the colonoscopy, he had no bleeding at all for quite a while, and I was wondering if it's because they cleaned him out and his insides got a "break".  I'm freaking out that nothing will show up on the RAST and we'll have NO idea what's going on.  I hate that feeling.
I'm rambling

, please share your thoughts and experiences.  I really appreciate the input.