13 month old son, sweat test 56. only has breathing issues, no other symptoms of cf and does not taste salty. any hope that he could be negative?

Needs DNA testing: Detection of mutation involving cftr gene in chromosome 7 is the most definitive test.

Maybe: The results listed are abnormal but sometimes testing variables arise that make a test less reliable. Having the test run at a certified test center is more dependable than those of community hospitals, primarily because of the volume of tests run.A secondary test looking for 25 mutations in the ctfr gene is also available but its accuracy varies among different ethnic groups.

Repeat CF sweat test: I would suggest having the test done again at a CF center and confirming that the collection of sweat was adequate. In addition, if a genotype test confirms the exact mutation, this is useful information. There are more than 1000 mutations though, and a sweat chloride test is considered a good screening test to detect cf. I hope that this helps. Prmg pediatric resp fax 8582599689 for ?S.