Hi, I'm 23 years old and I've had nasal polyps for a couple of years and get a chest infection every now and again. I was recently sent for a sweat test as my ENT thought it was strange for me to have nasal polyps at such a young age. The results of the sweat test came back as a 58? The ENT said this is an "intermediate results but it's very likely that I have cystic fibrosis". My GP called today to say that I'm being referred to a CF centre now and that they might do the sweat test again as it wasn't conclusive and that I mightn't have CF. Does anybody know if results can fluctuate so wildly from 58 to below 40? That seems like a crazy jump. I'm very unfamiliar with CF so would appreciate any information. Thanks!