1. Microbiology Department, Papanikolaou General Hospital, 570 10, Thessaloniki, Greece
2. Infectious Disease Unit, Papanikolaou General Hospital, 570 10, Thessaloniki, Greece
3. Department of Medical Microbiology, Center of Infectious Diseases, Leiden University Medical Center, European Study Group of C. difficile (ESGCD), 2333ZA, Leiden, The Netherlands
4. Microbiology Department, Agios Pavlos General Hospital, 551 34, Thessaloniki, Greece
5. Department of Microbiology, Aristotle University of Thessaloniki, Medical School, 541 24, Thessaloniki, Greece