There are no guarantees -- only guess work with CF, but generally speaking, yes I would have to say it's "better" to go 5 years without very many symptoms so far. Many people are quick to point out that someone can go from "just fine" to seriously ill very quickly, but there are some very definite rules for assigning "mild" "moderate" and "severe" CF -- it has to do with numerous things including lung function, nutritional absorption, number of hospitalizations per year etc.
I have no problem stating that my kids are "mild" - my son has almost no symptoms and only uses Flonase for sinus problems. He has had a couple of lung infections following a cold but has not cultured anything to treat yet so has never been on antibiotics (he is now 20 years old) My daughter had numerous lung infections per year until after her diagnosis, now, because she is able to take better care of her lungs (Pulmozyme, Hypertonic Saline, Flovent) and uses "The Vest" for clearance, she only has a few infections per year (like 1-2 now, as compared to 5-9 per year before) She has never been in the hospital and has only had to have oral antibiotics and Tobi (inhaled antibiotics)
Sounds like if the only problem you are having is sinus polyps, you are in pretty good shape so far! People with CF range from those who are seriously ill from their birth to those who have never spent time in the hospital. There is such a wide range of health issues. Keep in close contact with a certified CF clinic, keep yourself informed, educated and aware.
Count yourself lucky for the doctors being willing to pursue testing and determine he does have CF - there are many people who go for years with sick children who's doctors don't think the baby is sick enough or showing enough CF symptoms to test them. As devastating and upsetting it is to get the diagnosis of CF, the good news is your child will likely benefit from the correct treatment now and knowing what you are treating if/when other problems do come up is a whole lot easier to deal with when you know exactly what you are dealing with.
My daughter didn't have any symptoms until she was 5 years old too, and had they done the genetic testing then she would have been diagnosed at that age also. But it wasn't until she was 13 years old that we actually got the CF diagnosis because of the genetic blood test.
You can read my blog page for the complete story.
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