My 33 year old husband was just diagnosed with CF last year. Currently, his only symptoms are a positive sweat test and CBAVD (and yes, we only got this diagnosis after experiencing infertility). Based on his PFTs and x-rays, his pulmonologist says that his lungs are 'pristine.'
So at this point, we're just monitoring him yearly. His genetic mutations are DF508 and 5T, in case anyone's curious.