The host gastrointestinal microbiota is significantly influenced by antibiotic treatment which might favor Clostridium difficile infection (CDI), a frequent cause of community- and hospital-acquired, potentially life-threatening diarrhoea. CDI is followed by recurrence in 19-35% of patients despite adequate first line antimicrobial therapy. Currently there is no standardized therapy of recurrent or refractory CDI, but recent studies show remarkable effects of fecal microbiota transplantation (FMT).

In the current project, we aim to ideally match host and donor for FMT success in recurrent or refractory CDI. We will establish a clinical standard operating protocol for FMT, we will evaluate its safety and efficacy, and the patient acceptance and quality of life before and after FMT. We will analyse persistence of the donor microbiota within the recipient, define predictive clinical recipient and donor factors for FMT success and correlate them with microbial host and donor metagenomics.

We hypothesize that our work will yield novel, individualized strategies for recurrent or refractory CDI. In perspective, our results may be expanded to treatment of other inflammory bowel diseases.

Inclusion Criteria:

• recurrent or refractory CDI
• previous antimicrobial therapy includes at least on course of vancomycin 4x125 (or higher doses) for at least 7d
• CDI, defined as: 3 or more loose bowel movements/d AND (presence of C.diff. toxin in stools or toxin producing C. diff. strain) OR (endoscopic or histologic evidence of pseudomembraneous colitis)

Exclusion Criteria:

• no informed consent
• no ability to provide informed consent
• immune suppression (continuous immune-suppressive drugs; steroids: prednisolone-equivalent > 20 mg for 14d or longer)
• lack of appropriate donor
• pregnancy