What should I do about high ketones without high blood sugar?

Just to echo what some others are saying, whenever you are sick, you become insulin resistant -- meaning it requires MORE insulin to keep your blood sugars within range (and subsequently keep ketones suppressed). Often times, it is beneficial to increase insulin 15-25% to make up for this resistance. Make sure you are monitoring your sugars on a regular basis and correcting your highs as necessary -- this is where you may want to use your correction + ~15%. Of course, drinking lots of water is important because you want to flush the ketones out of your system!