My oldest dd was just diagnosed last year at the age of 11. For the past three years, she had problems gaining weight and then was having terrible stomach problems. We went to a gastro first, who did the whole stool sample (found out she had a lot of fat and protein in her stool - that was why she wasn't gaining), endoscopy and colonscopy, blood work, etc. Nothing showed up - they thought she had inflammatory bowel disease, crohen's or celiac. Nope, wasn't anyone of those!
My husband was at the dentist's office one day and our dentist asked about if she ever had a sweat test for CF. We both were like - no, she has never had lung problems, never! Talked to the gastro, she said, why not, it wouldn't hurt. Guess what, she had two positive sweat tests for CF. We were admitted to the CF Clinic (University of Michigan) and spent 4 days there. That was in Feb 2008.
Now, currently, her lungs at 100% clear, no problems. Her biggest problem is her digestive system. Still has problems gaining and keeping weight on. They did send her blood work to Mayo and they could not identify the CF mutation she has (there are over 1300 different mutations). She doesn't present like anyone our CF doctors has seen or have seen listed in their database. They still believe she has CF. We are trying to see a doctor in Canada who is doing a study on CF patients with mainly gastro problems. Hopefully, we can see him this summer.
Why won't your doctor order a simple sweat test? I would ask for that first before I would allow any invasive stuff done. I don't know where you are from, but make sure you have the sweat test done at a CF Center. If you want to know where they are, please PM and I can get you a list. The very best place for answers about CF is
www.cff.org - CF Foundation. That is the most up to date information.

to you, it was and has been a very bumpy road, but you will get through it.
Stacy