Data from a small randomized clinical trial indicate that fecal microbiota transplantation can reduce multidrug-resistant organism (MDRO) colonization in kidney transplant recipients, researchers reported this week in Science Translational Medicine.
In the phase 1 trial, a team led by investigators from Emory University School of Medicine enrolled and randomized 11 renal transplant recipients (RTRs) to receive FMT—a procedure in which stool from a healthy donor is transplanted to a patient—or an observation period followed by delayed FMT if stool cultures were MDRO positive at day 36. Kidney transplant patients are at high risk for MDRO colonization and infection, because they receive prophylactic antibiotics after transplant, which can select for MDROs. They are thus a priority for decolonization, because many of the antibiotics used to treat MDRO infections are nephrotoxic.
All 11 patients ultimately received at least one dose of FMT, with 9 receiving two treatments. While no participants in the observation group had spontaneous MDRO decolonization, 4 of 6 participants randomized to the FMT group were MDRO-negative after one dose, and 8 of 9 participants who received all protocol-specified FMTs were MDRO-negative by their last visit. In addition, at 180 days, FMT-treated participants had a longer time to recurrent MDRO infection compared with a control group of renal transplant recipients who did not receive FMT.
Bacterial strain competition
Analysis of Escherichia coli isolates from a subset of the FMT treatment group found that, rather than simply eradicating the MDRO strains, FMT appeared to promote competition with antibiotic-susceptible E coli strains that were present in the patients prior to FMT, with the susceptible strains replacing the MDRO strains.
"We conclude that microbiome therapies like FMT may provide a path to exploit bacterial strain competition to eradicate MDRO colonization," the authors wrote. "This trial also provided evidence that reducing MDRO colonization in RTRs could reduce recurrence of MDRO infections, which has broad potential to improve patient care and public health response and to reduce health care costs in patient groups beyond SOT [solid organ transplant] recipients."
We conclude that microbiome therapies like FMT may provide a path to exploit bacterial strain competition to eradicate MDRO colonization