With DS, his doctor indicated his baseline should be no cough. We were proactive and did chest physiotherapy. Mainly his symptoms were digestive and sinus, although he DID culture pseudomonas right away. He didn't cough, didn't cough up anything. Do this day he still doesn't cough up anything unless he has a cold. Unfortunately CF is a progressive disease and eventually the lungs will become affected due to infections, extra thick sticky mucus....
My daughter who is now 26 has a class1 and 2 mutation and she went undiagnosed till 10 years of age. She started showing symptoms at about 8 1/2 years old though but despite many worried trips to the pediatrician she went undiagnosed!
She is currently in the VX trial that was just approved yesterday (Trikafta) so I think I am free to put out there that this has helped her amazingly!
I am so happy that so many people will be helped by this drug.