. 2022 Nov 11;40(6):874–889. doi: 10.1007/s00774-022-01375-x

Table 1.

The main mode of operation, advantages and drawbacks of operative approaches for FMT

Approaches	Main mode of operation	Advantages	Drawbacks
Upper gastrointestinal pathway	1. Oral administration 2. Nasogastric tubes	1. Easy to perform and have relatively low overall risk 2. Protect the FMT materials from the gastrointestinal environment 3. No need for expensive instruments 4. Less damage to patients after repeated use 5. Well tolerated by patients, especially for the elderly patients 6. Reduce the potential probability of diseases transmission	1. Asphyxia may be caused by the bacterial fluid reflux or suction 2. If the human body itself has an obstruction, the transplanted bacterial fluid may not reach targeted intestinal tract accurately
Middle gastrointestinal pathway	1. Naso-intestinal tubes 2. Mid-gastrointestinal pathway-mediated TET	1. Reduce the bacterial translocation 2. Improve the efficacy of FMT 3. The mid-gastrointestinal pathway-mediated TET is convenient and easy to maintain 4. The mid-gastrointestinal pathway-mediated TET does not require further confirmation of the intestinal position by other medical instruments	1. The incidence of adverse events was relatively high, including diarrhea, cramp and constipation, and so on 2. It is expensive for the patients who require repeated FMT 3. It is accompanied with high risk of operation
Lower gastrointestinal pathway	1. Enema 2. Colonoscopy 3. Colonic pathway-mediated TET	1. Enema is a less invasive and relatively simple operation 2. It can completely display the situation of colon and biopsy suspicious tissues, which is conducive for the diseases staging 3. It allows operators to directly assess the intestinal inflammation and infuse a sufficient amount of donor fecal bacteria at the appropriate site 4. The gut microbiota can be accurately transplanted into the influenced intestinal segment, and the bacteria can further be retained in the targeted intestinal segment 5. Sufficient amount of donor fecal bacteria can be accurately infused, which can improve the treatment efficiency	1. Enema is accompanied with the risk of the bacteria of FMT is not able to reach the colon and splenic flexure 2. The incidence of adverse events was relatively high, including aggravating intestinal reactions and causing intestinal perforation 3. The patients with severe conditions may not able to tolerate colonoscopy transplantation or relevant anesthesia procedures 4. It is expensive for the patients who require repeated FMT

Approaches

Main mode of operation

Advantages

Drawbacks

Upper gastrointestinal pathway

1. Oral administration

2. Nasogastric tubes

1. Easy to perform and have relatively low overall risk

2. Protect the FMT materials from the gastrointestinal environment

3. No need for expensive instruments

4. Less damage to patients after repeated use

5. Well tolerated by patients, especially for the elderly patients

6. Reduce the potential probability of diseases transmission

1. Asphyxia may be caused by the bacterial fluid reflux or suction

2. If the human body itself has an obstruction, the transplanted bacterial fluid may not reach targeted intestinal tract accurately

Middle gastrointestinal pathway

1. Naso-intestinal tubes

2. Mid-gastrointestinal pathway-mediated TET

1. Reduce the bacterial translocation

2. Improve the efficacy of FMT

3. The mid-gastrointestinal pathway-mediated TET is convenient and easy to maintain

4. The mid-gastrointestinal pathway-mediated TET does not require further confirmation of the intestinal position by other medical instruments

1. The incidence of adverse events was relatively high, including diarrhea, cramp and constipation, and so on

2. It is expensive for the patients who require repeated FMT

3. It is accompanied with high risk of operation

Lower gastrointestinal pathway

1. Enema

2. Colonoscopy

3. Colonic pathway-mediated TET

1. Enema is a less invasive and relatively simple operation

2. It can completely display the situation of colon and biopsy suspicious tissues, which is conducive for the diseases staging

3. It allows operators to directly assess the intestinal inflammation and infuse a sufficient amount of donor fecal bacteria at the appropriate site

4. The gut microbiota can be accurately transplanted into the influenced intestinal segment, and the bacteria can further be retained in the targeted intestinal segment

5. Sufficient amount of donor fecal bacteria can be accurately infused, which can improve the treatment efficiency

1. Enema is accompanied with the risk of the bacteria of FMT is not able to reach the colon and splenic flexure

2. The incidence of adverse events was relatively high, including aggravating intestinal reactions and causing intestinal perforation

3. The patients with severe conditions may not able to tolerate colonoscopy transplantation or relevant anesthesia procedures

4. It is expensive for the patients who require repeated FMT

FMT fecal microbiota transplantation, TET trans-endoscopic enteral tubing