Testing young kids for carrier genes

anonymous

New member
When I was pregnant in 2001, my husband's brother had a baby diagnosed with CF. So my husband and I went for CF carrier screening. My test stated negative for the 100+ most common cystic fibrosis mutations. My husband's test identified the "delta F508 CF mutation in heterozygous form" in his DNA, meaning he was a carrier.

I have a 3 year old daughter and a 5 year old son. They exhibit no CF symptoms. I know at some point they need to be tested to determine if they are carriers (since my husband is a carrier).

Should I get them tested now? Although I'm not a carrier of one of the common mutations, I suppose I could be a carrier of a rare mutation. I'd rather wait until they are old enough to give blood without screaming and squirming, but could I be running a risk of not finding something that could be managed earlier instead of later?

Would it be better to just get them sweat tested, to rule out actually having CF, and then they can find out whether they are carriers when they are teens?

Thanks, Maria
 

oliver68

New member
We have had our 2 older kids tested with the sweat-test. we don't know yet wether they are carrier or not. We will wait for the next blood analysis (if any check is needed for any reason) to be done and ask for our mutations to be searched. However if they want to know before that time, we will have them checked. But this is because we know both of our mutations, mine is rare.

The risks for your kids to be CFers are low now that you have been checked for 100 mutations you know.
I think you can wait and see when they are older for the blood analysis. For the sweat test, if it makes you feel better, go ahead :)
 

anonymous

New member
There's a good chance that doing a sweat test on my kids would not make me feel better. But I have health insurance, so I might just do it anyway.

I'm assuming that if they don't display any symptoms because they potentially have only a mild case of CF, then the sweat test might be negative anyway, even if they do have CF.

Am I correct in thinking that if the case of CF is mild, then the likelyhood of a negative sweat test is greater?

Maria
 

anonymous

New member
Hi, i'm new to all of this - I went yesterday to an ENT for my sons chronic sinusitis and he informed me that my son displayed all of the symptoms for cf and had he ever been tested - i was in the least suprised, when i got home and found out more about it i was overwhelmed - and now i'm not sure how to get the answers i want the fastest - i have an hmo insurance policy and everything has to be approved to qualified and this could take forever and to be honest i just really want to know right ow. is that even possible? thanks for anything you can offer..lisa
 

anonymous

New member
Lisa, if your ENT is affiliated with a children's hospital that has an accredited cf clinic (or for that matter, ANY hospital as long as it has an accredited cf clinic), request that your ENT order a sweat test ASAP. They're easy, relatively painless and cheap (less than $100). You can usually get the answers back the same day, or at the latest, the following day. And, I would think as long as the HMO were in network, as cheap as a sweat test is, it wouldn't have to have prior authorization. How old is your ds?

Also, just because he has symptoms does NOT mean he has cf either. DEFINITELY get him tested but try not to stress too much. My ds is 6-1/2. He has asthma, allergies, severe chronic sinusitis, silent reflux, and is very small for his age but does NOT have cf. DS was near the top of the growth charts and relatively healthy for the first couple of months of his life but when he started daycare, we started the endless cycle of wheezing, ear infections, sinus infections, pink eye, pneumonias/lung infections, and non-stop coughing. He quickly fell down on the growth chart and did not recover even when we removed him from daycare a few months later. At birth, he was 90% for weight, now he's barely on the chart between 3 & 5%. By his second b-day, he was on albuterol in the nebulizer more days than not, and had already had 23 rounds of antibiotics for various lung/ear/sinus infections. At 3, our ex pediatrician (do NOT ask me why I stayed with the man for so long!), anyway, he referred him to an allergist who immediately diagnosed him with chronic sinusitis, asthma, and sent him for a sweat test which thankfully, came back negative. After a year of trying to figure out WHY his sinuses were so bad and HOW to fix them medically, he finally gave up and referred us to an ENT who removed his tonsils, adenoids, and did sinus surgery to clean them out & widen the natural openings so they would drain better. At the time, he said ds's sinuses were filled with thick "glue-like" mucous. When a few months later, despite aggressive prophylactic treatment, ds's sinuses were in the same shape as before, our ENT requested that we have ds tested genetically for cf. Our ENT is the main ENT that the local cf clinic refers their patients to so he has extensive experience with cf patients and felt like there was a good chance that ds's sweat test could have been wrong. By this time we had changed pediatricians and our new family doctor had referred ds to a pediatric pulmonary clinic that also happens to be an accredited cf clinic. The pedi-pulmo agreed that we should have ds tested further. The genetic test was negative & ds is not even considered a carrier. They did NOT do the AMBRY panel so there's a part of me that still occasionally worries about cf (why I still lurk here I guess). Despite my paranoia (for lack of a better term), all of his current drs consider him cf-free and he is doing somewhat better on advair 500, nasonex, nasal washes, zyrtec, prevacid, singulair, and allergy shots. Anyway, I shared my story because I remember how scary it was waiting for the results both times, especially since the drs seemed so sure that ds had cf. Our lab said they sweat test 200+ children every year and only a very small fraction come back positive. Definitely get him tested but try not to worry too much. I hope that helps.

Oh, and one more thing, did the ENT mention nasal polyps? According to our pedi-pulmo, children with nasal polyps are more likely to have cf than children with chronic sinusitis that do NOT have nasal polyps. Would you mind sharing your ds's story?
Noel
 

oliver68

New member
The "level" of the sweat test does not reflect the CF. It's not because the result is high that the CF is serious.
I don't know if I make myself very clear, but I assume you will guess what I mean ;-)
 

anonymous

New member
Hi Maria,

I agree with Oliver about sweat testing. The results will give you two numbers (one for each arm). Numbers under 40 are considered negative, from 40-60 borderline, and 60+ positive.

Our CF nurse practitioner basically said that true negatives are usually under 20. She said they sometimes do further testing on people with results in the 30's especially if they show symptoms. Borderline scores are always given further testing (DNA or a repeat sweat test).
(This is what they do at our clinic, I don't know if it is true everywhere.) To give you an example, my daughter with cf had results of 88 and 92, my other two daughters scored in the low teens (11, 12).

If you go to an accredited CF center, and your children score low (under 20), I think it should give you some peace of mind. Especially if they show no symptoms of CF.

Another Maria (mother of three daughters, the youngest w/CF)
 

anonymous

New member
I am kind of confused but some of these messages. If you kids have CF, even if it is a rare mutation, the sweat test should be conclusive. My son has 2 rare mutations. My husband and I both carry rare ones and he is possibly the only one with this combination. Although it is rare and appears to be a mild case, his sweat test was still over 80 and 90. No matter what your husbands tests showed up, your kids will only show systems of CF if you are carrier as well and you both gave the 2 genes to your kids. Being a carrier does not show anything up. My one question is why were you only tested for 100 mutations when their is at least 1000 identified mutuations. The easiest would be to do a sweat test on both of your children and then wait until they are older and can tolerate blood tests to find out if they are carriers. That is what we did with our other son. His sweat test was negative so we will test him later for carrier status. There is a good chance that you are not a carrier so you would have nothing to worry about until your children marry and want to have their own children. Then, they would need to know.
 

MasonsMom

New member
Anonymous poster-
It has been my experience that even carriers show symptoms. My son and my husband both have 2 mutations, but because both of these mutations are on one chromosome they are considered carriers. They very definitely show symptoms and my son is even taking enzymes due to the digestive problems.

Velvet
 
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