decreased lung function without exacerbation?

[amber682]

DS(7) normally gets 115-120% on his PFT's. 3 weeks ago and again today he got 100%. The doctor says it's still 100%, but concerning to have such a big drop. He hasn't really been sick, not culturing anything new, no cough. He cultures PA and steno on and off and does Tobi, but hasn't had any exacerbations. He also has a large asthma component to his CF, and we have been referred to an ENT for chronic sinus disease. His nasal passages often appear red and inflamed. But he has no cough at baseline and no nasal symptoms. We're going to try Cayston instead of the Tobi.

I'm kind of worried. What can cause a drop like that besides illness?

 

[welshwitch]

Hi there! There are a myriad of things that can cause this.

1. Sinus disease for sure. Has he gone to the ENT to check for polyps? IF your sinuses are inflamed then you can get post nasal drip, which leads to a whole new cycle of congestion.

2. The machine and/or the numbers they are using to measure PFTs. I did my PFTs today and they were 10% lower than normal. Naturally, I freaked out. It was my first time blowing on a new machine, and the doc said that the new one has caused discrepancies in people's numbers. THEN she took a closer look at the numbers. My height had been entered in incorrectly. This will change the predicted FEV, which in turn will change the measurements. This is the second time this has happened (other times, my age was in wrong, or weight. All these variables will change the outcome).

3. Blowing technique. As a kid it took me years to get consistent readings. If I blew a lower number than usual, my mom would be extremely upset. I began to learn that blowing hard=good numbers= happy mama. It wasn't until my teens and 20's that I really "got" the significance of high numbers and why it was so important to master the technique. Standing up, nose clips, bending over until there is no more air out are my tricks.

I wouldn't let it worry you too much. Get the other stuff checked out and then go back and try again.

 

[CFSanDiego]

After a virus, my daughter's pfts dropped from fev1 116 to 88. I completely freaked. Dr. tried a post xopanex pft to see if it went up....98%. Still not good enough. 2 weeks later it had gone up to 96 pre/ 106 post (still not good enough). He said she had reactive airway disease from a virus. Anyway, we put her on flovent. One month later we tested again. Fev1=122%. Small airway, incidentally, which were always in the 80's, were up at 119%. Soooooo she clearly had some inflamation going on which the flovent resolved. Now I am afraid to stop the stupid stuff. Maybe you can try this for awhile and see if it works?

 

[amber682]

welshwitch- I wasn't too concerned the first time bcause he was just getting over a little cold, or I thought it could have been a fluke or he was being silly, etc., but when it came up low today I got a little worried. We have a referral to see the ENT, they should call me within a couple of days. He does have issues with post nasal drip every single time he gets a cold. But thank you, your post made me feel better.

CFSanDiego- he is currently on Flovent, has been for quite a while. We used to do nebbed pulmicort but they let us switch to save some time. Maybe we should get back on the neb til his numbers come up

 

[welshwitch]

I would tackle the sinus issues first, and then keep eliminating other factors.

I'm 33 and getting my PFTs done stress me out every time. Keep fighting the fight!