Nasal Potential Difference

[veggiebin]

I was wondering if anyone on here has had a nasal potential difference test done. How uncomfortable is it? Can anyone compare it to a vocal chord dysfunction test where they put a camera down through your nose? Just wondering if it is worth having it done, the doctor suggested it because sweat tests have been negative even though two mutations are present.

 

[fel]

One of my sons had it -- he found it about the same as the camera probe from an ENT (which I can say from experience is pretty uncomfortable if you have a lot of inflammation like I do). But the test was not very useful -- came out borderline, while the sweat chloride test came out positive for CF (over 60 4 out of 5 times, 1 time in high 40's). Also we had to drive several hours to get it done. Definitely not worth it.

 

[veggiebin]

Fel -

Thank you for the reply. The doctor is suggesting it because her sweat chlorides come back low, we've had it done twice, but she has two rare mutations. Before doing any tests, the doctor told her that clinically he would say she has cf. We are trying to determine whether or not the symptoms are related to cf or something else. Because of the rarity of the mutations, it is unclear as to whether or not they are the culprit.

We will take your opinion into account when determining if she should do it. Thanks again!