I'm sorry to hear of your son's recent diagnosis. You didn't say how old he is, but I hope you are catching it early and he's doing well overall. Definitely follow up with your doctor with any questions (and you will also get a lot of good feedback from this forum). I hope you are seeing a pulmonologist at a certified CF Care Center--very important.
Ratatosk mentions pseudomonas aeruginosa (PA), which is a common infection in CF, especially as they get older. Over time, it can develp resistance to drugs, which has happened in my childrens' case. It's really important to regularly see your CF doctor (the protocal is every 2 months while healthy and more often when symptoms flare) and see what is culturing so you can act quickly to fight infection. Also keeping on top of respiratory treatements/chest PT (even when feeling well and having few symptoms) is important.
About treating infections, once you have a culture of a confirmed bacterial infection, the lab should also test different classes of antibiotics for senstivity -- basically what in the drug arsenal will kill the bacteria in the lab. The best approach is to attack the bugs with the lowest-level drug that will work to leave room later for more powerful drugs as resistance grows. PA is notorious for developing resistance, as well as other classically resistant bugs, like MRSA and some staph.
Best to you and your son.
Sherri
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