Basically, my son is two and exhibits a lot of the symptoms for CF. He was recently hospitalized with sinusitis and a mastoid infection due to his sinuses not draining...this was what finally convinced the doctor that it was time to screen for CF. I have read a lot on CF, and it seems like the sweat test is most used, but there are a lot of people who get a normal sweat test, and then later (after genetic testing) find out they do have it. With all his symptoms, it seems that a sweat test is kind of like using "the middle man." Is it worth it to bypass the sweat test and go straight to the genetic testing?