Post from JennifersHope is good. Definitely check with your doc. The first things that come to my mind are ...
1. Sometimes your blood sugars will shoot up when you are coming down with a cold or other sickness, or when (sorry) you are having an exacerbation of symptoms in your lungs.
2. If you haven't starting taking insulin yet, you may just be getting to the point that you need to start. Diabetes with CF <u>should</u> come on very slowly (due to very gradual harm to the pancreas), but for me it just showed up all of a sudden. If you're worried about having to start taking insulin, don't! Taking insulin shots is a lot easier than you think. The needles you use for insulin are extremely thin and short, so they hurt a lot less than a typical flu shot or whatever. Also, you don't inject insulin into your muscle, so that makes it hurt less also.
There's a big upside to taking insulin. I was always very skinny and not that healthy before I started taking insulin. But once I started taking insulin, I got up to normal weight and my health is great. So don't fear it too much. Feel free to contact me at dgraettinger@netzero.net.