The registry collects cases of patients received fecal microbiota transplantation (FMT) due to Clostridium difficile associated diarrhea (CDAD). The main objective of this study is to analyze the safety and effectiveness of FMT. Furthermore, data analysis will be used to implement a standardization of FMT in German hospitals and improve patient outcome. Therefore, a detailed description of completions of FMT are documented on our web-based survey platform www.ClinicalSurveys.net.

Concerning the documentation of patients received fecal microbiota transplantation (FMT) due to Clostridium difficile associated diarrhea (CDAD), physicians from all German hospitals performing a FMT are invited to provide prospective and retrospective information on these cases. Documentation of patient is performed by using the web-based survey platform www.ClinicalSurveys.net which was set up by researchers of the University Hospital of Cologne. This survey platform enables an optimal performance in epidemiological, observational, and interventional trials and is characterized by layered access security and frequent data backup. It has been used for numerous registry and cohort studies with approval of competent authorities and ethics boards.

The following data items are retrospectively or prospectively documented into our database, depending on if a informed consent exists or not:

• Patient characteristics (age, gender, weight, height, underlying disease)
• Indication for FMT
• Administration of antibiotics, chemotherapy, and immunosuppression prior to FMT
• Bowel movement prior to FMT
• Screening prior to FMT
• Description concerning completion of FMT
• Basic informations of the donor
• Outcome
• Prospective long term follow up (10 days, four weeks, three months, six months, and 24 months)

The following two differences of data documentation are observed:

1. Retrospective data documentation:

   Data of patients without an informed consent are documented strictly retrospectively after completion of the FMT. No pseudonymization of patient data is carried out so that no re-identification is possible.

2. Prospective data documentation:

Data of patients with an informed consent prior to FMT are documented prospectively. A pseudonymization of patient data allows a post-FMT contact (by writing or phone) to patients with respect to the 10 days, four weeks, three months, six months,and 24 months follow-up.

Inclusion Criteria:

• Patients with Clostridium difficile associated diarrhea

Exclusion Criteria:

• Patients < 18 years old

Patients with recurrent Clostridium difficile infection