This thesis investigates the strain distribution and characteristics of Clostridium difficile recovered from patients with sporadic and recurrent diarrhea. Samples were collected from patients with both recurrent and sporadic disease and ribotyping was conducted to determine the strain distribution, in particular examining the prevalence of NAP1/027. Antimicrobial susceptibility to vancomycin and metronidazole was determined using E-tests. It was found that both gender (female) and NAP1/027 were positively associated with recurrent disease. For patients undergoing human biotherapy for treatment of recurrent disease, pre and post-treatment samples were ribotyped. It was found that NAP1/027 was present in high proportions in individuals after clinical cure, however, no association was determined between the presence of C. difficile and response to fecal microbiota transplantation (FMT)treatment.