Sterile fecal filtrates, rather than FMT, may be sufficient for treating C. diff
Sterile fecal filtrate transfer was effective for treating five patients with recurrent Clostridium difficile infection, according to a pilot study conducted in Germany.
These findings suggest that transferring sterile filtrates from donor stool, rather than living fecal microbiota, may be sufficient for treating these patients, as non-living bacterial or viral components could be the active agents.
“With FMT, considerable amounts of stool water containing dead bacteria, their debris and their metabolites are transferred in addition to the living microbiota,” investigators wrote. Considering the diversity of effective FMT-related treatments for CDI, they aimed to determine if these ingredients in fecal water alone have clinical efficacy.
To do so, they obtained stool samples from five donors selected by five patients with symptomatic chronic-relapsing CDI at the department of internal medicine at the University Hospital Schleswig-Holstein in Kiel, Germany. They then prepared the samples as conventional FMT preparations, sterile-filtered them to remove small particles and bacteria, and transferred the filtrate to patients via nasojejunal tube.
Symptoms quickly resolved and stool habits returned to normal in all five patients, and remained so throughout 6 months follow-up.
While the researchers also performed microbiome, virome and proteome analyses, they could not clearly define an exact mechanism of action. However, these analyses showed long-term changes in microbial and viral community structures in FFT recipients.
They concluded that these preliminary findings warrant a comparison of FFT and FMT in a controlled setting, as FFT may be an alternative approach that could be particularly useful in immunocompromised patients. – by Adam Leitenberger
Disclosures: Two of the researchers report they are employed by CONARIS Research Institute AG, and another reports he is a shareholder of CONARIS, has been a consultant to Allergosan, Danone and Nestlé, and has received lectureship compensation from Allergosan. Two of the researchers also report they have lectured for Allergosan.