FarRed,
You should be getting checked as Patricia and Lee mentioned. There is a funnel machine that you pee into and it prints out a chart showing the flow and volume.
Then they use a scanner to see how empty your bladder is as soon as you are finished.
I have never had a neobladder bladder infection (but now I'm scared because I've said it writing so watch me come down with one tomorrow)!
However, whenever a different doctor sees me about something else and asks for urine test, they freak out. We, as folks with neobladders, can have our cultures show up looking like world war III, but unless there are other symptoms (fever, pain, malaise, etc.) it isn't really an infection. There is a difference between infection and colonization.
Anyway, you clearly have an INFECTION! Hope you cultures are done soon and they get you on the right antibiotics. If they put you on some heavy duty antibiotics you might want to eat yoghurt (if you can stomach that stuff) or get the acidophilus to take along with it because the antibiotics can kill all of the good bacteria that your gut needs.
Hope they get this under control soon. Sounds like maybe the course of antibiotics was not long enough and the infection is coming back stronger. I'm sure you know to always finish the course and not stop taking them just because you feel better, so my assumption is they may not be giving you high enough doses for a long enough time. This can cause the bacteria to build a resistance to the antibiotics and a different antibiotics is needed.
If your uro can't get it under control soon, then maybe an infectious disease specialist would be worth a visit.
Good luck with this! Sorry to hear about the continued problem.
Mike