Nasal Potential Difference as Part of CF Dx process

Beccamom

New member
My 11 year old has been in the diagnostic process for Cystic Fibrosis.  Today she had her second Nasal Potential Difference test as part of this process.  We know she has the G542X mutation M470V polymorphism and 8G>C polymorphism as well as 7T and 9T variants.  The first NPD test showed significant decrease in CFTR function, but her baseline number was not indigitive of CF.  Tonight I was told her baseline was significantly more negative than her previous NPD test.  My daughter was hosptialized for a respirtatory infection 2 days after teh 1st test  and I was told the swelling in her nose could have made the baseline normal on the first test.  I am anxiously waiting for the docotor to intrepret the results. 
So far I found the following information on John Hopkins website that leads me to believe she will have her diagnosis soon.  <a href="http://www.hopkinscf.org/main/whatiscf/diag_testnasal.html">http://www.hopkinscf.org/main/whatiscf/diag_testnasal.html</a>
Three specific features of the NPD test distinguish patients with CF:
1. A more negative baseline potential difference.2. A larger inhibition of NPD after addition of amiloride.3. Little or no change in NPD after addition of the chloride-free and isoproterenol solutions.
If anyone has experience with NPD testing as part of the CF diagnostic process I would appreciate any feedback.
 

Beccamom

New member
My 11 year old has been in the diagnostic process for Cystic Fibrosis. Today she had her second Nasal Potential Difference test as part of this process. We know she has the G542X mutation M470V polymorphism and 8G>C polymorphism as well as 7T and 9T variants. The first NPD test showed significant decrease in CFTR function, but her baseline number was not indigitive of CF. Tonight I was told her baseline was significantlymore negative than her previous NPD test. My daughter was hosptialized for a respirtatory infection 2 days after teh 1st test and I was told the swelling in her nose could have made the baseline normal on the first test. I am anxiously waiting for the docotor to intrepret the results.
So far I found the following information on John Hopkins website that leads me to believe she will have her diagnosis soon. <a href="http://www.hopkinscf.org/main/whatiscf/diag_testnasal.html">http://www.hopkinscf.org/main/whatiscf/diag_testnasal.html</a>
Three specific features of the NPD test distinguish patients with CF:
1.A more negative baseline potential difference.2.A larger inhibition of NPD after addition of amiloride.3.Little or no change in NPD after addition of the chloride-free and isoproterenol solutions.
If anyone has experience with NPD testing as part of the CF diagnostic process I would appreciate any feedback.
 

Beccamom

New member
<p>My 11 year old has been in the diagnostic process for Cystic Fibrosis. Today she had her second Nasal Potential Difference test as part of this process. We know she has the G542X mutation M470V polymorphism and 8G>C polymorphism as well as 7T and 9T variants. The first NPD test showed significant decrease in CFTR function, but her baseline number was not indigitive of CF. Tonight I was told her baseline was significantlymore negative than her previous NPD test. My daughter was hosptialized for a respirtatory infection 2 days after teh 1st test and I was told the swelling in her nose could have made the baseline normal on the first test. I am anxiously waiting for the docotor to intrepret the results.
<p>So far I found the following information on John Hopkins website that leads me to believe she will have her diagnosis soon. <a href="http://www.hopkinscf.org/main/whatiscf/diag_testnasal.html">http://www.hopkinscf.org/main/whatiscf/diag_testnasal.html</a>
<p>Three specific features of the NPD test distinguish patients with CF:
<p>1.A more negative baseline potential difference.<br />2.A larger inhibition of NPD after addition of amiloride.<br />3.Little or no change in NPD after addition of the chloride-free and isoproterenol solutions.
<p>If anyone has experience with NPD testing as part of the CF diagnostic process I would appreciate any feedback.
 

mom2owen

New member
Hi, I really cannot tell you anything about the NPD but I am also anxiously awaiting other's responses. Where did you have it done? I want to do it with Owen too but I am worried about where to go for it. I am also concerned, especially after reading your post, because his nasal passages are always inflammed/swollen. Maybe we need to wait until the spray he is using might help reduce that before we do the NPD.
How did your daughter handle the test? I sure hope you get answers soon.
 

mom2owen

New member
Hi, I really cannot tell you anything about the NPD but I am also anxiously awaiting other's responses. Where did you have it done? I want to do it with Owen too but I am worried about where to go for it. I am also concerned, especially after reading your post, because his nasal passages are always inflammed/swollen. Maybe we need to wait until the spray he is using might help reduce that before we do the NPD.
How did your daughter handle the test? I sure hope you get answers soon.
 

mom2owen

New member
Hi, I really cannot tell you anything about the NPD but I am also anxiously awaiting other's responses. Where did you have it done? I want to do it with Owen too but I am worried about where to go for it. I am also concerned, especially after reading your post, because his nasal passages are always inflammed/swollen. Maybe we need to wait until the spray he is using might help reduce that before we do the NPD.
<br />How did your daughter handle the test? I sure hope you get answers soon.
 

hmw

New member
We were told the same thing you were- that illness could yield results falsely indicative of 'no cf' due to how the swelling etc affects the tissues lining the nasal passages. When my son had his scheduled, the nurse checked in with us regarding his health several times in the weeks preceding our appt- if he were even slightly sick, we would have had to reschedule. His ended up being normal (baseline as well as response to the solutions added), and he's been deemed a 'symptomatic carrier.' His sister has CF. The test was necessary for him due to his sister having only one known mutation- he has the mutation too. She had a very high sweat test and clear symptoms, but he had borderline sweat tests (highest was 54), asthma (pft's lower than my daughter!) and other issues, so we needed to do something to try and figure this out with a higher degree of certainty.

He went to CHOP for his; they are doing a research study there re. using NPD as part of the diagnostic process and we were able to get Shawn into that. We could have gone to Hopkins as well- Emily's dr talked to their director about it- but I liked the idea of participating in the research study in the hopes that studies like that will eventually help get this test more widely available.

Mom2Owen~ you'll have to talk to them about the nasal meds if you are able to get it scheduled for Owen. I had to discuss Shawn's meds with the person I was talking to and they needed him off certain things for a while before the test.
 

hmw

New member
We were told the same thing you were- that illness could yield results falsely indicative of 'no cf' due to how the swelling etc affects the tissues lining the nasal passages. When my son had his scheduled, the nurse checked in with us regarding his health several times in the weeks preceding our appt- if he were even slightly sick, we would have had to reschedule. His ended up being normal (baseline as well as response to the solutions added), and he's been deemed a 'symptomatic carrier.' His sister has CF. The test was necessary for him due to his sister having only one known mutation- he has the mutation too. She had a very high sweat test and clear symptoms, but he had borderline sweat tests (highest was 54), asthma (pft's lower than my daughter!) and other issues, so we needed to do something to try and figure this out with a higher degree of certainty.

He went to CHOP for his; they are doing a research study there re. using NPD as part of the diagnostic process and we were able to get Shawn into that. We could have gone to Hopkins as well- Emily's dr talked to their director about it- but I liked the idea of participating in the research study in the hopes that studies like that will eventually help get this test more widely available.

Mom2Owen~ you'll have to talk to them about the nasal meds if you are able to get it scheduled for Owen. I had to discuss Shawn's meds with the person I was talking to and they needed him off certain things for a while before the test.
 

hmw

New member
We were told the same thing you were- that illness could yield results falsely indicative of 'no cf' due to how the swelling etc affects the tissues lining the nasal passages. When my son had his scheduled, the nurse checked in with us regarding his health several times in the weeks preceding our appt- if he were even slightly sick, we would have had to reschedule. His ended up being normal (baseline as well as response to the solutions added), and he's been deemed a 'symptomatic carrier.' His sister has CF. The test was necessary for him due to his sister having only one known mutation- he has the mutation too. She had a very high sweat test and clear symptoms, but he had borderline sweat tests (highest was 54), asthma (pft's lower than my daughter!) and other issues, so we needed to do something to try and figure this out with a higher degree of certainty.
<br />
<br />He went to CHOP for his; they are doing a research study there re. using NPD as part of the diagnostic process and we were able to get Shawn into that. We could have gone to Hopkins as well- Emily's dr talked to their director about it- but I liked the idea of participating in the research study in the hopes that studies like that will eventually help get this test more widely available.
<br />
<br />Mom2Owen~ you'll have to talk to them about the nasal meds if you are able to get it scheduled for Owen. I had to discuss Shawn's meds with the person I was talking to and they needed him off certain things for a while before the test.
 

Mistyjo

New member
<blockquote>
The CF dr we saw mentioned doing this test with my daughter.  He said if everything else comes back normal or not showing anything then we will do this test.  Did she have a hard time doing the test?  If they always have a runny nose does that affect the test?
</blockquote>
 

Mistyjo

New member
The CF dr we saw mentioned doing this test with my daughter. He said if everything else comes back normal or not showing anything then we will do this test. Did she have a hard time doing the test? If they always have a runny nose does that affect the test?
</blockquote>
 

Mistyjo

New member
<p>The CF dr we saw mentioned doing this test with my daughter. He said if everything else comes back normal or not showing anything then we will do this test. Did she have a hard time doing the test? If they always have a runny nose does that affect the test?
</blockquote>
 

Beccamom

New member
Harriet, we also went to CHOP for the NPD through the clinical trial. It is great that your son is an asymptomatic carrier. Sorry your daughter has been through so much. My other daughter has no known mutations just 7T and 9T variants and maybe polymorphisms.

Mistyjo, The following is the link for the clinical trial using NPD in the diagnostic process for Cystic Fibrosis that is being conducted at the Children's Hospital of Philadelphia.

http://clinicaltrials.gov/ct2/show/NCT00589745

As far as the actual procedure the clincal coordinator was absolutely wonderful with my daughter. We had to do the test 2 times because the first time was inconclusive, but based on my non-medcial internet search and staring at the numbers last night I am very confident that she will get the diagnosis next week. I know the baseline numbers did change this time since she wasn't sick and they became more negative which I found online is indicative of Cystic Fibrosis. I found that the Hopkins website gave a thorough description and understanding of the NPD process and results.

http://www.hopkinscf.org/main/whatiscf/diag_testnasal.html

My daughter is 11 and did very well during the actual procedure. We requested a numbing cream for IV needle which doesn't go into the vein just under the skin, but she is soooo skinny that we wanted the cream. The rest was totally not painful at least from what my daughter has told me. It did take about 1 1/2 hours of sitting still for the testing after the 20 minutes to numb her hand. She watched TV the entire time. The rest consists of 5 liquids dripping into and immediately running out of the nose. We were told that CHOP has been successful with children as young as 10, but the test could be done with a younger sedated child, but CHOP to my knowledge has not actually done that.
 

Beccamom

New member
Harriet, we also went to CHOP for the NPD through the clinical trial. It is great that your son is an asymptomatic carrier. Sorry your daughter has been through so much. My other daughter has no known mutations just 7T and 9T variants and maybe polymorphisms.

Mistyjo, The following is the link for the clinical trial using NPD in the diagnostic process for Cystic Fibrosis that is being conducted at the Children's Hospital of Philadelphia.

http://clinicaltrials.gov/ct2/show/NCT00589745

As far as the actual procedure the clincal coordinator was absolutely wonderful with my daughter. We had to do the test 2 times because the first time was inconclusive, but based on my non-medcial internet search and staring at the numbers last night I am very confident that she will get the diagnosis next week. I know the baseline numbers did change this time since she wasn't sick and they became more negative which I found online is indicative of Cystic Fibrosis. I found that the Hopkins website gave a thorough description and understanding of the NPD process and results.

http://www.hopkinscf.org/main/whatiscf/diag_testnasal.html

My daughter is 11 and did very well during the actual procedure. We requested a numbing cream for IV needle which doesn't go into the vein just under the skin, but she is soooo skinny that we wanted the cream. The rest was totally not painful at least from what my daughter has told me. It did take about 1 1/2 hours of sitting still for the testing after the 20 minutes to numb her hand. She watched TV the entire time. The rest consists of 5 liquids dripping into and immediately running out of the nose. We were told that CHOP has been successful with children as young as 10, but the test could be done with a younger sedated child, but CHOP to my knowledge has not actually done that.
 

Beccamom

New member
Harriet, we also went to CHOP for the NPD through the clinical trial. It is great that your son is an asymptomatic carrier. Sorry your daughter has been through so much. My other daughter has no known mutations just 7T and 9T variants and maybe polymorphisms.
<br />
<br />Mistyjo, The following is the link for the clinical trial using NPD in the diagnostic process for Cystic Fibrosis that is being conducted at the Children's Hospital of Philadelphia.
<br />
<br />http://clinicaltrials.gov/ct2/show/NCT00589745
<br />
<br />As far as the actual procedure the clincal coordinator was absolutely wonderful with my daughter. We had to do the test 2 times because the first time was inconclusive, but based on my non-medcial internet search and staring at the numbers last night I am very confident that she will get the diagnosis next week. I know the baseline numbers did change this time since she wasn't sick and they became more negative which I found online is indicative of Cystic Fibrosis. I found that the Hopkins website gave a thorough description and understanding of the NPD process and results.
<br />
<br />http://www.hopkinscf.org/main/whatiscf/diag_testnasal.html
<br />
<br />My daughter is 11 and did very well during the actual procedure. We requested a numbing cream for IV needle which doesn't go into the vein just under the skin, but she is soooo skinny that we wanted the cream. The rest was totally not painful at least from what my daughter has told me. It did take about 1 1/2 hours of sitting still for the testing after the 20 minutes to numb her hand. She watched TV the entire time. The rest consists of 5 liquids dripping into and immediately running out of the nose. We were told that CHOP has been successful with children as young as 10, but the test could be done with a younger sedated child, but CHOP to my knowledge has not actually done that.
 

hmw

New member
Shawn loved the fact that he created a complete electrical circuit once he was hooked up, lol... he's quite the little scientist. <img src="i/expressions/face-icon-small-smile.gif" border="0"> He did not have any pain with the needle on his arm; it is placed very shallow, barely under the skin and taped in place. It was very time consuming as posted above and he got bored with all the sitting still but nothing hurt. He's done nasal sprays for a long time so the stuff flowing in his nose didn't upset him. What DID drive him nuts was not being able to blow his nose when he felt like he needed to... he could wipe his nose, and sneezed incessantly, but could not blow! <img src="i/expressions/face-icon-small-smile.gif" border="0">

I agree, the clinic coordinator IS a wonderful person (I am sure the same person you worked with.) I have nothing but good to say about her or the center in regards to our experience with this.
 

hmw

New member
Shawn loved the fact that he created a complete electrical circuit once he was hooked up, lol... he's quite the little scientist. <img src="i/expressions/face-icon-small-smile.gif" border="0"> He did not have any pain with the needle on his arm; it is placed very shallow, barely under the skin and taped in place. It was very time consuming as posted above and he got bored with all the sitting still but nothing hurt. He's done nasal sprays for a long time so the stuff flowing in his nose didn't upset him. What DID drive him nuts was not being able to blow his nose when he felt like he needed to... he could wipe his nose, and sneezed incessantly, but could not blow! <img src="i/expressions/face-icon-small-smile.gif" border="0">

I agree, the clinic coordinator IS a wonderful person (I am sure the same person you worked with.) I have nothing but good to say about her or the center in regards to our experience with this.
 

hmw

New member
Shawn loved the fact that he created a complete electrical circuit once he was hooked up, lol... he's quite the little scientist. <img src="i/expressions/face-icon-small-smile.gif" border="0"> He did not have any pain with the needle on his arm; it is placed very shallow, barely under the skin and taped in place. It was very time consuming as posted above and he got bored with all the sitting still but nothing hurt. He's done nasal sprays for a long time so the stuff flowing in his nose didn't upset him. What DID drive him nuts was not being able to blow his nose when he felt like he needed to... he could wipe his nose, and sneezed incessantly, but could not blow! <img src="i/expressions/face-icon-small-smile.gif" border="0">
<br />
<br />I agree, the clinic coordinator IS a wonderful person (I am sure the same person you worked with.) I have nothing but good to say about her or the center in regards to our experience with this.
 

dragonlady

New member
My daughter also tried the Nasal Difference at Hopkins, but she said it was uncomfortable and couldn't tolerate the thing so far back in her nasal passage.  It was only for certification training and not diagnostic, so we didn't feel the pressure to continue with the test if it made her uncomfortable.
 

dragonlady

New member
My daughter also tried the Nasal Difference at Hopkins, but she said it was uncomfortable and couldn't tolerate the thing so far back in her nasal passage.It was only for certification training and not diagnostic, so we didn't feel the pressure to continue with the test if it made her uncomfortable.
 
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