I am so sorry you are going through this period of waiting, waiting! My oldest is in a bit of 'limbo' too with borderline sweat tests (also done at a CF-accredited facility; it was so good you took your child there for his second- as you found out that DOES make a difference when they know what they are doing!!), a couple mild symptoms and we know he's at least a carrier but not whether he carries the second, unknown mutation in our family so I can relate to what that is like. He's 11 too and we are trying to track down the results of his newborn screening- so far without success- the hospital told me they only archive for 10yrs so they may have been destroyed and he probably was not screened for CF anyway (no one seems to know this either!) It was not mandatory in our state and was done on a very 'spotty' basis over the last 15yrs.
I'm so glad that the genetic test was sent out to Ambry and that is was not one of the less-comprehensive screening tests that only looks for a few (i.e. 100ish) mutations, as there are more than 1,500 of them! Ambry is your best shot at an accurate dx when it comes to the gene testing part of it... it finds both mutations for about 99% of those w/ CF. My daughter and her cousin (both of whom have a definitive dx) each have one known and one unknown mutation. I only make that point because not finding both mutations cannot always rule out CF <i>in the presense of other diagnostically relevant symptoms.</i>
Wishing the very best outcome for your son and a clear answer one way or the other.
