How To Treat Dizziness And Hearing Loss While Taking Avelox For Sinus Infection?

I have CVID, am on infusion therapy for just 2 mos. Long history of sinus infections & surgeries. 2 mos ago culture showed MRSA in sinuses. Currently treating for newly cultured heavy growth of enterobacter (not sure which strain) and pseudomonas in sinuses. I'm allergic to Cephalosporins, cannot tolerate Augmentin, & have had dizziness & hearing loss while on long course of Avelox 11-18 mos ago. Currently Prescr Bactrim 800. How dangerous is this infection for me, and what is likely to get rid of it? Thank you.