Background: In renal transplant recipients, carbapenem-resistant Klebsiella pneumoniae  (CRKP) infection is a common complication, and usually associated with severe clinical outcomes due to a lack of effective treatment.
Case Presentation: A 37-year-old woman with CRKP infection one month after kidney transplantation was involved in this study. Microbial characteristics of fecal samples from the patient were analyzed. Fecal microbiota transplantation (FMT) was performed for treating the CRKP infection. One week after FMT, the patient’s urine and anal swab cultures returned negative for CRKP, and 17 days after FMT, the incision showed complete healing. Moreover, the patient had no symptoms of infection two months after FMT. Alpha diversity analyses showed that before FMT, the patient was associated with obviously lower species richness and diversity than the donor, which significantly increased at one week, three weeks and two months after FMT. Beta diversity analyses showed that though the patient’s microbial community post-FMT still differed from the donor composition, their distances decreased visibly, especially at one week and three weeks after FMT. Obvious shift in microbial composition could be observed before and after FMT. The microbial composition of the patient post FMT resembled the donor composition. Relative abundance of genera such as Phascolarctobacterium  and Lachnoclostridium  increased after FMT, while the relative abundance of Klebsiella  significantly decreased.
Conclusion: This study demonstrated the therapeutic effect of FMT on infections caused by CRKP for a renal transplant patient. Further studies are required to confirm the findings of this study.
Keywords: carbapenem-resistant Klebsiella pneumoniae , infection, fecal microbiota transplantation, gut microbiota