Newbie with Lots of Questions


New member
So my son has always been in the 2-5% range for weight and height. Despite being born after his due date, he was so tiny, and knowing I have genes for big people in my family, we were surprised. He also struggled to breath immediately and was whisked away to the ICU upon birth. He quickly recovered though and was brought to me within a few hours. As a baby, I breastfed him, and unlike his sisters, he just didn't eat much. I tried formula thinking maybe it was that he didn't want to work for it. It was the same thing. Fast forward a few years and it is pretty much the same thing. He is so skinny and underweight. He can't seem to keep up with his younger sister. We had to take him out of soccer because he just couldn't keep up. When he walks, he lags behind us and always complains of being tired. In first grade, he had his first pneumonia. Since then, he has had two more. He's finishing 3rd grade now. The doctor is now giving him a sweat test that he should be able to take in the next week. If it is negative or borderline, what should I insist on next?

I really never thought CF was a possibility. I asked my dad if there was anyone with CF in the family. He said my mother's cousin was diagnosed with it in high school and that she died at the age of 40.

I had a 23 and me test a long time ago, so I checked that out. I was only able to find the following below. Could someone help me understand what it means? I know this is not a diagnosis... and that I would need a certified test. This is only to get some hunches. Could this mean I'm a carrier? Am I out of the woods?


23andMe blog cystic fibrosis having the CT genotype at rs7817 showed worse lung function than people with either two Cs or two Ts at this SNP. Identification of IFRD1 as a modifier gene for cystic fibrosis lung disease


[PharmGKB:Curated This variant in the IL1B gene was associated with lung disease severity categories (P < 0.10) and longitudinal analysis of lung disease severity (P < 0.10) in a study of 808 cystic fibrosis patients, suggesting IL1B may be a clinically relevant modulator of CF lung disease.]
more info
1 Magnitude
0.1451 GMAF
1 Publications
IL1B Gene
2 Chromosome
112831216 Position
2015-01-01 Rs Modified
minus Stabilized
minus Orientation

Oddly, I have very salty sweat. When I run, a cake of salt will develop on my face, arms, legs, etc... even on my clothes, white rings of salt will appear as the sweat dries. Anyway, I would love to hear your thoughts and I'm grateful for this forum. I feel a little helpless and praying CF is not the case for my little boy. He is my sunshine.


Staff member
23 & me only tests for the most common CF mutations -- I think they test for 32...? And there are over 1600 mutations for CF. So it's hard to say if you are a carrier or have a 2nd mutation without more extensive testing.

Usually a sweat test is done to start the ball rolling. Even if your son's results come back as negative or borderline, he still has health issues, so I would ask "if not CF, then what". Will the seat test be done at an accredited CF facility? How are his stools --- does he have issues with loose, frequent, bulky, greasy ones? If so, should they run a fecal fat test for pancreatic insufficiency. Can they run a sputum or throat culture to see if he's culturing any cf bugs? What about blood work -- vitamin levels (ADEK). Have they done any blood work to test for other things such as anemia, diabetes....?