This is a real-world study to explore the safety and the efficacy of washed microbiota transplantation （WMT） for patients with Clostridioides Difficile Infection （CDI）.

At least 12 subjects who meet all the inclusion criteria but do not meet any exclusion criteria will be enrolled in this study. Data of demographic characteristics, intestinal symptoms, medicine treatment usage and clinical outcomes will be collected. After treatment, they will enter the follow-up period （at least for 4-week post-WMT）for safety and efficacy evaluation. Subjects with no response and recurrence will receive salvage therapy, and the extended follow-up period will be performed.

Inclusion Criteria:

Subjects must meet all of the following inclusion criteria to enter the study:

1. At the time of informed consent, male or non-pregnant or non-lactating female.

2. The diagnostic criteria for C. difficile infection are met during screening:

   1. Medical records confirming CDI prior to screening (laboratory tests are positive for Clostridium difficile or its toxin): Clostridium difficile toxin test is positive (determined by EIisa test), or colonoscopy indicates pseudomembranous enteritis; Or Glutamate dehydrogenase positive, toxin negative, there are obvious causes and diarrhea.
   2. CDI-related diarrhea episodes, i.e., defecation ≥3 times/day for at least two consecutive days with unformed stools (Bristol score 6-7).

3. The subject or his/her legal representative gives informed consent, fully understands the purpose of the study, is able to communicate effectively with the investigator, and comprehends and complies with the requirements set forth in the study.

Exclusion Criteria:

Subjects meeting any of the following exclusion criteria must be excluded from the study:

1. Subjects with immune deficiencies (such as HIV infection, or neutrophils <0.5×109/L in absolute value, or lymphocytes <0.5×109/L, etc.), or on immunosuppressants, or on medium to high doses of steroid hormones (≥20g/d of prednisone or equal doses of steroid hormones).
2. There is rectal outlet obstruction (such as rectal mucosal prolapse) or significant intestinal stenosis assessed by the investigator and colonic transendoscopic enteral tubing cannot be performed.
3. Confirmed or clinically suspected infection with pathogenic microorganisms other than Clostridium difficile prior to screening.
4. Have had major abdominal surgery (other than laparoscopic gallbladder or appendectomy), previous partial or total colectomy, previous partial small intestinal resection, or previous gastroduodenal surgery within 6 months prior to screening.
5. At the time of screening, the subject or his/her legal representative refuses to take effective contraception within 3 months after the last treatment.
6. According to the judgment of the investigator, the subjects are not suitable to participate in this clinical study, or participation in this clinical study cannot guarantee the rights and interests of the subjects.

National patients with CDI receiving WMT will be enrolled.