I'm a C-6 quad for about 15 years and have a SP catheter. During those years i've had many many UTI's, but never once felt sick because of them. Not fevers, no feeling crappy, pretty much nothing.
The reason i'd know when i had UTI's were i'd get dysreflexia more often and the biggest tell tale sign was urine that smelled horrible along with more sediment floating around in it. In fact, i've yet to remember a time where a urine sample was taken for whatever the reason and i didn't have at least a lower level UTI and other times had a raging UTI. Yet physically, i'd have never known i had a UTI because there were never any other signs.
Because i so often have cloudy/smelly urine, but am not sick otherwise, i avoid going to the doctor about it because if i took antibotics each time i think i had a UTI, i fear that i'd become immune to the antibotics. So long as i'm not outwordly sick or i don't sense the UTI at the time is that bad (only kinda strong smelling urine/cloudy), does it matter that much if i often have a UTI going on, but it's not making me otherwise ill?