The study aims to evaluate the safety and efficacy of fecal microbiota transplantation (FMT) for the treatment of steroid resistant graft-versus-host-disease (GVHD) of the gut. This strategy might offer a safe and effective therapeutic approach for these patients with a poor prognosis and limited therapeutic options.

Graft-versus-host-disease (GVHD) is a major complication after hematopoietic stem cell transplantation (HSCT). Gut is the most vulnerable target organ of acute GVHD. Patients who develope the acute gut GVHD and do not respond to the first line therapy with steroids have a high mortality. The investigation of safe and effective second line therapy for these patients are in need. The study evaluates safety and efficacy of fecal microbiota transplantation (FMT) for the treatment of streoid resistant GVHD of the gut. Stool for FMT will be prepared from the healthy donor.This strategy might offer a safe and effective therapeutic approach for these acute steroid resistant gut GVHD patients.

Inclusion Criteria:

• 1. Adults(ages are elder than 18 years and younger than 75 years) who developed gut acute Graft-versus-Host Disease(aGVHD) after allogeneic hematopoietic stem cell transplantation(HSCT) and were resistant to a first line therapy with steroids.

  2. patients who were diagnosed as Stage 3 or 4 Gastro-intestinal Acute Graft-versus-Host(GI-aGVHD) with the symptoms such as diarrhea or abdominal pain.

  3. Participants who accepted the FMT treatment. 4. Signature of informed and written consent by the subject.

Exclusion Criteria:

• 1. patients who were diagnosed as Stage 1 or 2 Gastro-intestinal Acute Graft-versus-Host(GI-aGVHD) 2. patients with unstable vital signs or severe cardiac and pulmonary disorder. 3. patients who were failure to cooperate endoscopy examination. 4. patients who were younger than 18 years or pregnant. 5. patients who were poor compliance to FMT treatment. 6. patients who were not able to give informed consent.