9 years since borderline sweat & 1 gene mutation found. Retest??

[kaylinsmom]

Hi, I’m back on here stalking all of the forums looking for answers. It’s been quite a while since I posted last. A quick refresher, my daughter had 2 sweat tests done in 2010 with results of 40 & 44. Genetic testing was done and showed the gene G576A and 7t,7t. She was followed by a pulmonologist for about 7 years. They never diagnosed her with cf but were puzzled by her health problems. She has undergone many tests. To make this short, she had recurring pneumonia, digestive issues, sinus infections, ear infections, and is currently have severe upper abdominal pain. We are suspecting gallbladder. She goes for an ultrasound in a few days. She is 17 now and hasn’t had lung problems (besides a chronic cough) or sinus issues for a few years now. She was diagnosed with POTS 2 years ago. She is extremely pale, sweaty hands and feet. I guess the reason I’m here is to see if retesting would change the results since it has been 9 years? Does your sweat levels change over time? I know more mutations are found regularly, so should she have genetic testing done again? I was looking up gallbladder function and for pediatric gallbladder problems it said it could be related to cf!? I should mention that all her testing was done at an accredited cf center. MUSC in Charleston, SC. Thanks for any advice! I am very thankful for this site and all of the information I have attained for you all.

-Erin

 

[kenna2]

Sweat tests can change, but genetic testing does not. Genetic testing is the only 100% accurate way to determine if someone has CF. Some people have had low sweat tests results, but are still diagnosed with CF when genetic testing is done.

 

[DougB]

For years genetic testing could only detect 1 mutation for me, I then had my doctor send my sample to Johns Hopkins for a trial that would try and detect the second mutation in people diagnosed with CF with a sweat test but had only 1 detectable mutation. They were able to find my second mutation. You might want to reach out to the CF clinic again to see if this is a possibility for your daughter.

 

[roeann]

Kaylinsmom, there are about 1700 mutations that cause CF. I know the test my son had only checked for about 100 or so genes. Most are not tested for, I would check with Johns Hopkins as they say their test ID's 98% of the mutations (I am not sure how many mutations that represents). You might want to check this page out https://www.cff.org/Care/Clinician-Resources/Mutation-Analysis-Program/

 

[kaylinsmom]

Thank you for the replies. Her genetic testing was done through ambry or mayo. I can’t remember but it took forever because they tested for the first 100 and then tested for more with duplicates or something. Sorry, my memory is fuzzy after almost 10 years. I was just curious if there has possibly been more genes found in the last 9 years that they didn’t know about when my daughters was checked? Her ultrasound showed no stones but we may have to have another type of scan to check the function of the gallbladder. Thanks again.

 

[Ratatosk]

I'm sure more genes have been identified in more recent years, but even 10 years ago there were well over 1500. It's just more cost effective to do a sweat test and test for the most common mutations and unless you push for answers, further testing usually isn't done

 

[rtorres25]

For years genetic testing could only detect 1 mutation for me, I then had my doctor send my sample to Johns Hopkins for a trial that would try and detect the second mutation in people diagnosed with CF with a sweat test but had only 1 detectable mutation. They were able to find my second mutation. You might want to reach out to the CF clinic again to see if this is a possibility for your daughter.

Hi! How long ago was the Johns Hopkins testing? I also have only 1 identified gene, L206W. Mine was sent to them in 2016. They didn't find my other gene. I'm wondering if it was the same trial, but hopeful it was more recent? I would love to know my other gene.

 

[DougB]

Hi! How long ago was the Johns Hopkins testing? I also have only 1 identified gene, L206W. Mine was sent to them in 2016. They didn't find my other gene. I'm wondering if it was the same trial, but hopeful it was more recent? I would love to know my other gene.

I believe mine was done in 2016 as well.

 

[Kangaroo15]

You might want to get your genes sent to ambry in California who can run the entire sequence of Chromosome 7 where CF occurs. We are seeing less severe types of CF in people.

 

[findcure]

“You might want to get your genes sent to ambry in California who can run the entire sequence of Chromosome 7 where CF occurs. We are seeing less severe types of CF in people.”

This is the best solution if cost is not an issue. Sequencing is getting cheaper and cheaper with the advancement of technologies.
I feel obligated to say something about CF in general to avoid confusion when we talk about it. CF is caused by mutations in a single gene, called CFTR (Cystic Fibrosis Transmembrane Conductance Regulator), which encodes a fairly large protein. More than 2000 mutations have been identified in this gene. However, not all mutations cause CF.
Since one in every 35 Americans is a symptomless carrier of the defective CFTR gene, it is advisable for couples planning to have children to take the test for the purpose of making informed decision. If a couple are both symptomless carriers, their child has about 25% chance to get the disease.

 

[Printer]

Hi, I’m back on here stalking all of the forums looking for answers. It’s been quite a while since I posted last. A quick refresher, my daughter had 2 sweat tests done in 2010 with results of 40 & 44. Genetic testing was done and showed the gene G576A and 7t,7t. She was followed by a pulmonologist for about 7 years. They never diagnosed her with cf but were puzzled by her health problems. She has undergone many tests. To make this short, she had recurring pneumonia, digestive issues, sinus infections, ear infections, and is currently have severe upper abdominal pain. We are suspecting gallbladder. She goes for an ultrasound in a few days. She is 17 now and hasn’t had lung problems (besides a chronic cough) or sinus issues for a few years now. She was diagnosed with POTS 2 years ago. She is extremely pale, sweaty hands and feet. I guess the reason I’m here is to see if retesting would change the results since it has been 9 years? Does your sweat levels change over time? I know more mutations are found regularly, so should she have genetic testing done again? I was looking up gallbladder function and for pediatric gallbladder problems it said it could be related to cf!? I should mention that all her testing was done at an accredited cf center. MUSC in Charleston, SC. Thanks for any advice! I am very thankful for this site and all of the information I have attained for you all.

-Erin

She should be seen by a CF SPECIALIST at an APPROVED CF CLINIC.

 

[Printer]

Sweat tests can change, but genetic testing does not. Genetic testing is the only 100% accurate way to determine if someone has CF. Some people have had low sweat tests results, but are still diagnosed with CF when genetic testing is done.

When I was diagnosed, two years before the gene was discovered, there was no genetic testing. The test base began at 32 mutations, a standard that remains in use today. The base has grown from 32 to nearly 3000 mutations. Over the years genetic testing has expanded therefore changed. It is extremely important that the patient (family) determine how many mutations were included in the test. A CF test could be for the most common (32) mutations and test negative thus leaving the Doctors office confident that you or your child is free of CF. You do the math, testing for 32 or 250 etc, and not testing for every known mutation is not a full and accurate diagnosis.