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False Negative
- Thread starter anonymous
- Start date
Emily65Roses
New member
This didn't happen to me, as I was dx at 2 days old. And I don't know the chances, but I know I've heard of a lot of people this happened to. It changes given the results of the negative too. If your negative was a higher negative, the chances that it's false are clearly higher. I imagine this isn't of much help, but I just wanted to say that I hear about false negatives a lot. A false positive is impossible, from what I understand. But false negatives are quite common.
I too have heard of some false negaives, where the first test will show negative but the parents still aren't satisified so they ask for an additional sweat test, or a extended panel CF blood test (like from ambry genetics) and come to find out they do find the genes in the blood test, or the second sweat test is positive.
Julie (wife to Mark 24 w/CF)
Julie (wife to Mark 24 w/CF)
Thank-you for your responses.
My DD 3 1/2, was sweat tested at seven months old. It was negative.
She had slow weight-gain, always below the 5th percentile. She is on the charts now and doing well, but she is still sick and more often now, due to a large amount of mucous build-up. It was always blamed on other things, such as teething.
As it is getting really bad again lately, I have asked that we find out a cause. The Dr. put her on flonase to see if that helps. (It hasn't)
I am going to request her allergies be tested, and if that does not turn up anything, than I will request to have her re-tested for CF.
Thanks again,
Jen
My DD 3 1/2, was sweat tested at seven months old. It was negative.
She had slow weight-gain, always below the 5th percentile. She is on the charts now and doing well, but she is still sick and more often now, due to a large amount of mucous build-up. It was always blamed on other things, such as teething.
As it is getting really bad again lately, I have asked that we find out a cause. The Dr. put her on flonase to see if that helps. (It hasn't)
I am going to request her allergies be tested, and if that does not turn up anything, than I will request to have her re-tested for CF.
Thanks again,
Jen
midwestmama
New member
My son had maybe or 6 sweat tests--all negative. I followed my gut and insisted on more testing in which they did the blood test which was positive. His health and growth are so much better now. Our first test was not at a CF center. At the time I didn't know the difference. So follow your heart. If you're here asking you must have some doubts. Ask for the blood test.
Midwest mama, what genes does your ds have? Did they find them on genzyme's panel of 87 or did you do Ambry's extended panel? Do you know what your ds's sweat chloride #s were? We're in the process of genetic testing after a negative sweat test and I just wondered how common it was to have one neg, the other pos. Are your ds's mutations uncommon? Thanks.
midwestmama
New member
I believe both of his are DF508. The most common. (correct me if I'm wrong) We went through Ambry. At the first hospital that we went to that was NOT a CF clinic, the lab tech told us how all of the tests that she had ever done, came back negative. Now I assume that they are doing something wrong. ALL of my son's symptoms pointed to CF. So after I had done a little more investigating on the disease I contacted my -small town family Dr- and asked for a referral to our CF center. After our first appt, they suspected CF immediately and started testing. My son would not sweat enough for accurate results. They tried it over and over. So they did the genetic test and it took a couple of weeks for the results. In the meantime they tried steroids for allergies and a couple of other things. After we got him on vitamins, zantac, enzymes and an antibiotic, he was a different child.
Shelly
Shelly
Emeraldmirror
New member
I had 5 false negitives before they decided that i had a "hint" of cf.
Ashley 20 w/cf
Ashley 20 w/cf