Fecal microbiota transplantation influences procarcinogenic Escherichia coli in recipient recurrent Clostridioides difficile patients

BACKGROUND & AIMS: Patients with multiple recurrent Clostridioides difficile infection (rCDI) have a disturbed gut microbiota that can be restored by fecal microbiota trans-plantation (FMT). Despite extensive screening, healthy feces donors may carry bacteria in their intestinal tract that could have long-term health effects, such as potentially procarci-nogenic polyketide synthase-positive (pks+) Escherichia coli. Here, we aim to determine whether the pks abundance and persistence of pks+ E coli is influenced by pks status of the donor feces. METHODS: In a cohort of 49 patients with rCDI treated with FMT and matching donor samples-the largest cohort of its kind, to our knowledge-we retrospectively screened fecal metagenomes for pks+ E coli and compared the presence of pks in patients before and after treatment and to their respective donors. RESULTS: The pks island was more prevalent (P = .026) and abundant (P < .001) in patients with rCDI (pre-FMT, 27 of 49 [55%]; median, 0.46 reads per kilobase per million [RPKM] pks) than in healthy donors (3 of 8 donors [37.5%], 11 of 38 samples [29%]; median, 0.01 RPKM pks). The pks status of patients post-FMT depended on the pks status of the donor suspension with which the patient was treated (P = .046). Particularly, persistence (8 of 9 cases) or clearance (13 of 18) of pks+ E coli in pks+ patients was correlated to pks in the donor (P = .004). CONCLUSIONS: We conclude that FMT contrib-utes to pks+ E coli persistence or eradication in patients with rCDI but that donor-to-patient transmission of pks+ E coli is unlikely.