Fecal Microbiota Transplantation Contributes to Persistence or Clearance of E coli in Patients with rCDI

Fecal bacteria
Faecal bacteria. Scanning electron micrograph (SEM) of bacteria cultured from a sample of human faeces. At least 50 per cent of human faeces is made up of bacteria shed from the gut. Many of these bacteria are a normal part of the flora found in the intestines and are beneficial to digestion. However, some are pathogenic, such as Salmonella enterica and certain strains of Escherichia coli, which can cause foodborne illnesses. Magnification: x6000 when printed 10 centimetres wide.
Researchers aimed to determine the effects of FMTs from healthy donors on pks+ E coli in patients with recurrent Clostridioides difficile infections.

Fecal microbiota transplantation (FMT) contributes to persistence or clearance, but not transmission, of polyketide synthase (pks+) Escherichia coli (E coli) in patients with multiple recurrent Clostridioides difficile infections (rCDI). These findings are based on a study published in Gastroenterology.

FMT can restore the disturbed gut microbiota in patients with rCDI. Despite extensive screening, healthy donors may influence potentially procarcinogenic pks+ E coli in the gut of patients with rCDI. In this cohort study, researchers in the Netherlands set out to determine the effects of FMTs from healthy donors on pks+ E coli in patients with rCDI.

Investigators retrospectively screened fecal metagenomes for pks+ E coli and compared the presence of pks in patients pre and post treatment, and with their donors. All patients with rCDI (n=49) were aged between 27 and 92 years (median, 73.5 years), including 31 women and 18 men. All donors (n=8) were aged between 24 and 46 years (median, 33 years), including 4 women and 4 men. Samples were collected between April 2016 and March 2018.

The researchers found that the pks island was more prevalent (P =.026) and abundant (P <.001) in patients with rCDI (pre-FMT: 27/49 patients; 55%; median, 0.46 reads per kilobase per million [RPKM] pks) compared with healthy donors (3/8 donors; 37.5%; 11/38 samples; 29%; median, 0.01 RPKM pks).

The investigators identified a direct dependence between the post-FMT pks-status and pks in the donor suspension (P =.046).

Among pks+ patients, persistence (8/9 cases) or clearance (13/18) of pks+ E coli was correlated with pks in the donor (P =.004).

This study is not without limitations. The age differences of approximately 40 years between the donors and patients may have been a confounding factor in the study.

The researchers determined that FMT contributes to pks+ E coli persistence or eradication in patients with rCDI. However, it should be noted that the investigators found no clear evidence of donor-to-patient transmission of pks+ E coli.

“It is currently unknown how long pks+ E. coli persists in cured rCDI patients and on what time-frame this may contribute to colorectal carcinogenesis. Further research addressing the long-term health effects is needed to evaluate the cancer risk due to pks+ E. coli in rCDI and other patients, since this might offer opportunities for early intervention in the development of colorectal cancer,” the study authors wrote.  

Disclosure: Some study authors declared affiliations with the industry. Please see the original reference for a full list of authors’ disclosures.

Disclosure: This research was supported by Vedanta Biosciences. Please see the original reference for a full list of disclosures.


Nooij S, Ducarmon QR, Laros JFJ, et al, on behalf of the working group of the Netherlands Donor Feces Bank. Faecal microbiota transplantation influences procarcinogenic Escherichia coli in recipient recurrent Clostridioides difficile patients. Gastroenterol. Published online June 10, 2021. doi:10.1053/j.gastro.2021.06.009