TOPLINE:

Among patients with haematologic malignancies, faecal microbiota transplantation (FMT) was associated with an effective decolonisation of carbapenem‑resistant Pseudomonas, was well tolerated, and was linked to fewer severe infections shortly after treatment.

METHODOLOGY:

• This retrospective analysis in Poland assessed the efficacy and safety of FMT to decolonise carbapenem-resistant Pseudomonas in patients with haematologic malignancies and evaluated subsequent infectious outcomes.
• A total of 14 patients (median age, 42 years; 50% men) colonised with carbapenem-resistant Pseudomonas received FMT from rigorously screened donors, with FMT administered via gastroduodenoscopy in at least two doses approximately 9 days apart.
• Two cohorts were analysed — patients treated with FMT during ongoing chemotherapy (n = 6) and those treated with FMT as a decolonisation strategy before allogeneic haematopoietic cell transplantation (n = 8).
• The primary endpoint was the decolonisation of carbapenem-resistant Pseudomonas, defined as three consecutive negative rectal swab results after FMT; secondary endpoints focused on short- and long-term infectious complications after FMT.
• The median follow-up duration was 491 days.

TAKEAWAY:

• The overall decolonisation rate was 71%, with a median time to decolonisation of 14 days; 60% of responders remained decolonised through the end of follow‑up.
• Primary FMT failure occurred in four patients, and recolonisation after initial clearance was reported in four patients; the mean time to recolonisation from last FMT was 83 days.
• Among nine patients who developed carbapenem-resistant Pseudomonas infections, the most common manifestations were bloodstream infections (67%), soft tissue infections (56%), and gastrointestinal complications (56%); three patients developed severe infections within 30 days.
• During follow-up, seven patients died; six deaths were attributed to infectious complications, five of which were due to carbapenem‑resistant Pseudomonas. No significant treatment‑related adverse events were reported.

IN PRACTICE:

"FMT offers a compelling supportive intervention aimed at MDRO [multidrug-resistant organisms] decolonization, potentially severing the link between gut colonization and subsequent infection in vulnerable cohorts. The procedure is feasible in patients with hematologic diseases, with a favourable safety profile and minimal adverse events," the authors wrote.

SOURCE:

This study was led by Aneta Nowicka, Poznan University of Medical Sciences, Poznań, Poland. It was published online on January 31, 2026, in the International Journal of Infectious Diseases.

LIMITATIONS:

This study was limited by its retrospective design, the small sample size, and the lack of a control group. Heterogeneity in diagnoses, immune status, and antibiotic exposure among patients potentially confounded the assessment of FMT efficacy, and the absence of digital pharmacologic records prevented a detailed analysis of individual antibiotic exposure.

DISCLOSURES:

This study did not receive any grant from any funding agency. The authors reported having no competing financial interests or personal relationships that could have influenced the work.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.