Systematic review & meta-analysis of interventions targeting gut colonisation by MDRO, 2025

Abstract Background Gut colonisation with multidrug-resistant organisms (MDRO) increases risks of infection, transmission and mortality in healthcare settings. Although decolonisation strategies have been attempted to reduce the impact of gut MDRO, no consensus exists on their effectiveness. Our study evaluates the effectiveness of these strategies. Methods We searched PubMed, EMBASE, CENTRAL, CINAHL and Web of Science for randomised controlled trials (RCTs) published from Jan 2005 to Dec 2024. MDRO were defined as ESBL-E, CRE, VRE and MDR/XDR Gram-negative bacteria, excluding C. difficile and MRSA. Eligible studies included adults or children in healthcare settings, with baseline MDRO colonisation confirmed by rectal swab or stool sample. The primary outcome was reduction in colonisation rates in the short term (<4 weeks) and long term (≥4 weeks). A random-effects model was used for meta-analysis. Two reviewers independently screened studies, extracted data and assessed bias using the Cochrane RoB2 tool. PROSPERO: CRD42025625291. Results Of 900 studies screened, 14 RCTs met inclusion criteria - seven evaluated probiotics, six assessed oral non-absorbable antibiotics, and one examined a combination of antibiotics with faecal microbiota transplantation (FMT). Most were hospital-based (n = 13), with one in a long-term care facility. Meta-analysis of all studies showed no significant impact on short-term (RR 1.04, 95% CI 0.82-1.32) or long-term decolonisation rates (RR 1.12, 95% CI 0.95-1.33). Subgroup analysis showed no effect of probiotics or antibiotics alone although antibiotics showed a trend towards benefit for long-term decolonisation (RR 1.21, 95% CI 0.99-1.48). Risk of bias was low in four studies, with seven having some concerns and three at high risk. Conclusions Current evidence does not show a significant effect of intervention on short- or long-term gut MDRO decolonisation. Further trials are needed to evaluate promising strategies, including FMT and antibiotics. Key messages • Current evidence shows no significant short- or long-term benefit of interventions for gut MDRO decolonisation. • More robust trials are needed to identify sustained decolonisation strategies.