CF with negative sweat test

[Alyssa]

Laura -- glad to hear you are still following up with genetic testing.

Misty -- no, a sweat test in the low 100's probably does not really mean a more severe case -- there is some classification of gene mutations that can tell us a little bit of something, and sure the higher the number on the sweat test, the more "incorrectly" the body is functioning with whatever it does with sodium chloride, but everybody is so different with this disease I would not say her sweat test numbers mean a whole lot other than it could be a indicator of how much salt she is loosing and you need to be careful on hot days and activities that she will be sweating more -- she is more prone to dehydration than other people with no cf or w/cf but really low numbers.

 

[Alyssa]

Laura -- glad to hear you are still following up with genetic testing.

Misty -- no, a sweat test in the low 100's probably does not really mean a more severe case -- there is some classification of gene mutations that can tell us a little bit of something, and sure the higher the number on the sweat test, the more "incorrectly" the body is functioning with whatever it does with sodium chloride, but everybody is so different with this disease I would not say her sweat test numbers mean a whole lot other than it could be a indicator of how much salt she is loosing and you need to be careful on hot days and activities that she will be sweating more -- she is more prone to dehydration than other people with no cf or w/cf but really low numbers.

 

[hhhhhmom]

Hi Everyone,

No, I'm really not a nut (in that I'm not trying to "fit" my son's symptoms into cf--I know that it would be unlikely w/o a positive sweat test). . . BUT, in researching bronchiectases and primary immunodeficiency diseases, which my son has, I found an interesting article which applies here: http://adc.bmjjournals.com/cgi/content/full/82/6/481 It talks about a couple of different cases where cf has been found in kids w/neg sweat tests & the definitive testing that was done to verify that they actually did have cf. I wanted to bring it up because it talks specifically about tests that someone could request if they are still uneasy about a negative sweat test.

Laura
Mom of 4 boys, 1 girl
13 y-o boy w/diabetes and PID
8 y-o boy w/diabetes and poss PID

 

[hhhhhmom]

Hi Everyone,

No, I'm really not a nut (in that I'm not trying to "fit" my son's symptoms into cf--I know that it would be unlikely w/o a positive sweat test). . . BUT, in researching bronchiectases and primary immunodeficiency diseases, which my son has, I found an interesting article which applies here: http://adc.bmjjournals.com/cgi/content/full/82/6/481 It talks about a couple of different cases where cf has been found in kids w/neg sweat tests & the definitive testing that was done to verify that they actually did have cf. I wanted to bring it up because it talks specifically about tests that someone could request if they are still uneasy about a negative sweat test.

Laura
Mom of 4 boys, 1 girl
13 y-o boy w/diabetes and PID
8 y-o boy w/diabetes and poss PID

 

[thelizardqueen]

I've always heard that there's such a thing as a false negative, but never a false positive. If that makes any sense.

 

[thelizardqueen]

I've always heard that there's such a thing as a false negative, but never a false positive. If that makes any sense.

 

[Alyssa]

Ok, I didn't take the time to check out the site and read it but is the test you are talking about the nasal potential difference test by chance? That's the only other one I am aware of -- good test, but not available everywhere and is pretty much a pain in the neck to do -- involves a needle in the arm and dripping saline solution out of your nose......

 

[Alyssa]

Ok, I didn't take the time to check out the site and read it but is the test you are talking about the nasal potential difference test by chance? That's the only other one I am aware of -- good test, but not available everywhere and is pretty much a pain in the neck to do -- involves a needle in the arm and dripping saline solution out of your nose......

 

[icefisherman]

the sweat test i took was like having plstic wrap around you arm for a half hour. i was five so i don't remember specifics. is there other ways?

 

[icefisherman]

the sweat test i took was like having plstic wrap around you arm for a half hour. i was five so i don't remember specifics. is there other ways?