epoh, be sure to REALLY discuss those test results. RAST values are notorious for producing false positives-- most often for food, but also for pet and pollen/mold allergies.
With food, it's easy enough to conduct a challenge to find out for sure-- but with the others, it's more hit and miss and depends a LOT on patient history. BEFORE you go into that appointment, be sure to arm yourself with a thumbnail journal of when your child seems to have the most trouble. That is, under what circumstances, both general (early fall until frost) and particular (at Jenny's house, where there are three cats and a parakeet).
If you have seen no evidence that your dog is a problem, then it (probably) isn't. A positive allergy test really doesn't mean much with respect to tolerating a particular animal, unfortunately.
So as in my example with dustmite allergy, it's more a matter of seeing whether or not efforts to reduce exposure to that allergen have any discernable impact. That will trump test results every time. You obviously don't want to find a new home for your dog just to "see" if it helps, though! Pay close attention next time you travel, though, to see whether or not you see improvement when away from the dog-- or worsening symptoms when you return home to your dog.
Spirometry is hard when a kid is impaired, but there's no real reason that I know of why a physician wouldn't want to check it as a baseline measurement.
