Dx severe bladder wall infection been on alternating abx for two months with no improvement in symptoms, biopsy showed staph. why no improvement ?

Bacterial resistance: The staph may be resistant to the antibiotics given. A culture and sensitivity will help discern this. The fact that the antibiotics have been alternated for two months tells me that your urologist is putting a good faith effort in to fighting this infection. Make sure you follow up with the same urologist. Also, the infection could be cleared but the inflammation still persists.