sounder27 I believe it's a serious bacteria..... I have it in lungs and in sinus cavaties. I recently had sinus surgery because doctors thought perhaps I was getting excessive drainage into lungs. They cultured a sample from sinus and then asked me to use powdered Levaquin in a sinus wash twice daily for two weeks. I did that. I don't know if it got rid of the pro blem but I doubt it. I know that is the main bacteria in my lungs at this time. Apparently it's hard to get rid of. I've had other bacterias throughout the last few years but the pseudomonas has been the hardest for me. Don't know if this helps you at all but I'm sure there are many on here who can share more information.