I want to ditto everything Alyssa said and add our recent experience with sweat testing.
My husband recently went through CF testing because of some sinus/pulmonary issues that he had been having. His dr did a sweat test first...number came back 18. When he called with the results, he told us the number and immediatly said that this number does not rule out CF and that he had already put in orders for genetic testing.
Apparently, on the sweat test results (we never got a copy, but this is what the dr told us), there was a disclaimer that this test could not be used to rule out CF because people with "negative" results had later tested postive through genetic testing. I don't know what the exact wording was, but that was the idea the disclaimer conveyed.
(BTW, he was shown only to be a carrier on the Ambry complete test.)
But, the point is that sweat tests should never be used to rule out CF. They can be a quick way to diagnose, but should not be relied on to rule out CF.
My suggestion for you right now is to go with your gut feeling. If your doctor has other ideas of what might be causing your sons problems, go ahead and look into those. But, don't let this negative sweat test result cross CF of your list.
Maybe you can get a copy of the sweat test lab work and see if it has any kind of disclaimer. Or just ask your doctor to put in writing that this sweat test result DEFINATELY rules out CF. If he is not willing to do that, then he should order complete genetic testing for your son.
My husband recently went through CF testing because of some sinus/pulmonary issues that he had been having. His dr did a sweat test first...number came back 18. When he called with the results, he told us the number and immediatly said that this number does not rule out CF and that he had already put in orders for genetic testing.
Apparently, on the sweat test results (we never got a copy, but this is what the dr told us), there was a disclaimer that this test could not be used to rule out CF because people with "negative" results had later tested postive through genetic testing. I don't know what the exact wording was, but that was the idea the disclaimer conveyed.
(BTW, he was shown only to be a carrier on the Ambry complete test.)
But, the point is that sweat tests should never be used to rule out CF. They can be a quick way to diagnose, but should not be relied on to rule out CF.
My suggestion for you right now is to go with your gut feeling. If your doctor has other ideas of what might be causing your sons problems, go ahead and look into those. But, don't let this negative sweat test result cross CF of your list.
Maybe you can get a copy of the sweat test lab work and see if it has any kind of disclaimer. Or just ask your doctor to put in writing that this sweat test result DEFINATELY rules out CF. If he is not willing to do that, then he should order complete genetic testing for your son.