Is fecal transplant a solution to prevent antibiotic resistance in immunocompromised patients?

“One of the greatest threats against global health, food safety, and development.” This is how the WHO characterizes antibiotic resistance, which leads to longer hospital stays, higher medical expenditure and increased mortality. Among potential solutions under investigation, fecal microbiota transplant (FMT) brings hope to the fight against multi-drug resistant bacteria but still raises questions regarding its safety, especially in immunocompromised patients.

10 immunocompromised patients were tested

A monocenter study was based on the retrospective analysis of 10 patients with blood disorders, undergoing a bone marrow transplant and who were (or had been) colonized by carbapenemase-producing or vancomycin-resistant bacteria which were classified as very high risk (eXDR, emerging extensively drug-resistant bacteria). The patients were about to receive an allogeneic (the donor is not the same person as the recipient) hematopoietic stem cell transplant (HSCT) following the treatment of their hematological cancer. The FMT was performed by enema or nasogastric tube, either before (for four patients) or after (for the remaining six who were still receiving immunosuppressants at the time of the procedure) the allograft.

Confirmed efficacy

In 7 out of 10 cases, investigators observed a significant decolonization of multi-drug resistant bacteria (3 successive bacterial cultures were negative). In 6 out of 10 patients, this decolonization persisted during the entire follow-up period (4-40 months). The three failures could be explained by methodological difficulties (antibiotics could not be suspended 72 hours after the FMT, the treatment period was too short, or the stool sample was too little...). Finally, when the first FMT was not able to eradicate multi-drug resistant bacteria, a second transplant turned out to be possible and effective in 2 out of 3 cases.

Proven safety

In all 10 patients, FMT was not associated to any major risk: one patient was constipated in the first days following the transplant; two others had transient, mild diarrhea. According to the researchers, none of the 3 reported deaths was attributable to the FMT. In two cases, the disease had progressed; and in the third case, the patient received two fecal transplants because of severe GVHD (sidenote: GVHD Graft-versus-host disease )  following the hematopoietic stem cell transplant, and the treatment with immunosuppressants led to the onset of a viral and fungal infection 6 months after the FMT. Consequently, in patients infected with multi-drug resistant bacteria, FMT seems to be an effective and safe solution, even in cases of severe immunosuppression.