A fluctuation in your PSA level could be the result of an infection, and that is why your urologist is putting you on a coarse of antibiotics. I would imagine it's possible that one day your PSA is normal (2.0), and then you contract an infection the next day that causes your PSA to jump a point or two (4.7). Bad luck. Your urologist is making sure that's all it is before he schedules you for another biopsy. There are several members of our group that have had similar circumstances with their PSA tests, and I believe that in at least one case it was just an infection. I personally have a friend that posted a (1.8) jump in his PSA, and it too was apparently caused by an infection. However his urologist suggested monitoring his PSA level every 6 months as a precaution.
I certainly know how scary this all is, but you are doing the right thing by persistant PSA testing. It may very well turn out that you are like my friend, and he is quite relieved to know he's PCa free. But by the slightest of chances if it is an early diagnosed PCa then the cure rate is optimum.
I pray that you are just suffering a minor infection, and you won't ever have to join or group, but we are always here for support. Good luck to you.
Diagnosed at age 60
PSA went from 2.2 to 3.8 in 14 months
2 of 14 cores positive at 10%
Gleason 6(3+3), negative DRE, neg. boundaries
DaVinci surgery on 02/23/06