@twentyse7en I also got Cdiff from taking Clindamycin. My heart goes out to you. I also had tests come back negative and then was retested almost a week after and it came back positive for my 4th bout. I then was prescribed Dificid (fidaxamicin). That was last October and so far, I've been okay. My GI put me on S. Boulardii. It's a probiotic that can survive the acid in your stomach and get to the GI tract. You might ask your GI about it when you go tomorrow. I sure hope the Vancomycin works for you. I took it for 10 days also and then relapsed and did the Vanco taper for 6 weeks. Then after the 4th bout, I finally found something (Dificid) that seems to have killed the Cdiff spores. Please keep us posted how you are doing. I know exactly what you're going through.