My son is 16 yrs old with Cystic Fibrosis. He was diagnosed at 7 months of age. It is true that most are diagnosed early but a lot of research has been done in the last 10 years since the gene was found, that early diagnoses of asthma are being tested for CF and in turn has been rediagnosed with CF.
The true test will be the sweat test. They may have to do two sweat tests to diagnose, sometimes the first comes up in the gray area or borderline. Therefore, they may have to repeat the test, it then may come back just a bit higher and they will determine then he would have CF.
A mucous plug is what it is. A piece of thick mucous stuck in the little branches of the aveoli. What we do to remove a plug is place our son in a draining position. Place the body in a slanted position. Head and shoulders down and hips up. This can be done laying across your body with pillows on your lap and he places his hips on the pillows and his head on the couch or bed. If you remember where the plug was located (upper right, lower right, upper left, lower left)
"Clap" on this area for at leat 2 minutes, the most 6 minutes.
(Clap is to cup your hand and just tap, you will hear like a clapping noice and start a rythmn sound). By doing this you will loosen the plug and he will cough it up and out. This does not hurt him in anyway. If he does say it hurts, just give him tylenol for the pain.
My son leads a very normal life. He plays flag football and is the best player on the team. He has only been hospitalized 4 times in his whole life. Each CFer is different. Some it affects lungs, some digestive, some both.
If you have any further questions, let me know here or just pM me. I will be able to help address any concerns you may have.