Bladder Issues

Question
Hello Dana:
We have a spayed lop-eared rabbit who is approximately 6 years old.  Her name is Cookie.
Since we adopted her from the Humane Society 4 years ago, she has suffered from reoccurring bladder problems.
Her symptoms include: urinating on herself resulting in urine scald and loss of fur, increased appetite accompanied with weight loss.  
The first antibiotic she was given was Baytril, which worked very well.  Four months later, her illness returned.  Baytril was given again and cleared things up once again.  When her symptoms returned 5 months later, Baytril didn't work.
After trying numerous antibiotics with no success, we found that Zithromax worked very well.  She is currently at the end of this round of Zithromax, but has shown no improvement.
Over the years, she has had an x-ray to look for stones, urinalysis testing and a culture & sensitivity test done.
We were told that the bacteria found was Alpha Hemolytic Streptococcus and Staphylococcus Xylosus.
In the past she has been put on Metronidazole, Sulfatrim, Ivomec Injection, Cephalexin (very harsh), Chlor Palm and Lufeneron.  Unfortunately, this problem returns every 4-5 months and it seems to be tricky finding something to combat her symptoms.
She is a very healthy and happy rabbit at the best of times and we would appreciate finding an antibiotic that would take care of her reoccurring illness once and for all.
Thank you for your time.

Answer
Dear Valerie,

There is something odd going on if the bacteria keep coming back after so many different antibiotics.  There is no magic remedy for this, but you might consider asking the vet about products that could help boost her immune system (e.g, Equimune IV, or even just good ol' echinacea extract, which may or may not work).

Also consider cranberry extract, which does have bioactivity that makes the bladder walls less hospitable to bacteria.  It's used to aid in treatment of human bladder infections, and could work similarly in rabbits.  It's certainly worth a try.

But it might also be time for a new urinary culture, to be sure the identity of the bacterial population hasn't changed.  Also very important to use a high dose for the entire course to be sure as many bacteria as possible are killed, leaving little for her (apparently compromised?) immune system to handle.

Hope this helps.

Dana