Fecal Microbiota Transplantation for Steroid-Refractory Acute GI GVHD

Inclusion Criteria: 1. Stage II to IV steroid refractory acute GI-GvHD in allo-HSCT recipients 1. Stage II to IV acute GI-GVHD subjects, having \>1000 mL stool per day, diarrhea \> 5 times/day, or abdominal cramping, bleeding or ileus, AND 2. Resistant to a first-line therapy with corticosteroids (CS) <!-- --> 1. Lack of improvement after 5 days of treatment with CS at 2 mg/kg/d methylprednisolone or other CS with equivalent dose, 2. Progression after 3 days of treatment with CS at 2 mg/kg/d methylprednisolone or other CS with equivalent dose. 2. Age ≥ 18 years old. 3. Allo-HSCT with any type of donor, stem cell source, GvHD prophylaxis or conditioning regimen. 4. Allow vancomycin-resistant enterococcus (VRE) colonization and asymptomatic cytomegalovirus (CMV) viremia, which is defined as a detectable CMV viral load in plasma but without tissue-invasive disease. 5. Patients able to have a minimum of 12 hours discontinuation of systemic antibiotics in order to perform the allogeneic FMT (antiviral and antifungal agents are allowed) 6. Signature of informed and written consent by the subject or by the subject's legally acceptable representative for patients under guardianship or trusteeship. Subject must understand and voluntarily sign an informed consent form prior to any study-related assessments/procedures being conducted. Exclusion Criteria: 1. Absolute neutrophil count \< 500 cells/uL. 2. Absolute platelet count \< 30000 /uL which is not correctable by transfusion 3. Hemodynamically unstable status with the following conditions: systolic blood pressure \< 90 mm Hg, pulse oximeter oxygen saturation (SpO2) \< 90%, PaO2 \< 60 mm Hg, or respiratory rate \> 22/minute. 4. Uncontrolled and active infection from bacteria, virus, or fungus as determined by the investigators.