I am in a similar situation. Resistant to everything for past 2 years. I have been synergy tested. Every now and then I try IV antibiotics in hopes for some improvement, but so far it hasn't changed anything. I've heard that even though your resistant the antibiotics can help reduce inflammation. It hasn't worked for me. Last time I was on IV antiobiotics I talked extensively with the CF Pharmacist and he said in his experience he hasn't seen any cases of resistant bugs becoming susceptable to antibiotics again. But as others have reported their experiences have been more positive. Everyone is different, never give up hope.