2570. A Randomized Controlled Trial of Lactobacillus rhamnosus GG on Multidrug-Resistant Organism (MDRO) Colonization

BACKGROUND: MDRO present a greater threat to public health than ever before, and antimicrobial options are decreasing. Altered colonic microbiota following antimicrobial exposure allows for subsequent colonization by MDRO. Ingestion of prophylactic Lactobacillus rhamnosus GG (LGG) could be an approach to prevent the spread of, and subsequent infection due to MDRO, by promoting a healthy bacterial milieu within the colon. METHODS: This is a prospective, double-blinded, randomized clinical trial in which a total of 87 subjects on broad-spectrum antibiotics were randomized to receive LGG twice daily (n = 43) vs placebo (n = 44). Stool or rectal swab specimens were collected for culture at enrollment, every 3 days during admission, and at discharge. Selective media were used to detect the following MDRO: Clostridioides difficile (CD), vancomycin-resistant Enterococcus (VRE), and antibiotic-resistant Gram-negatives (GN). The primary outcome was MDRO acquisition. Secondary outcomes included analysis for loss of any MDRO if colonized at enrollment, and acquisition or loss of individual MDRO. RESULTS: Subjects in both groups had similar prevalence of colonization with any MDRO at study enrollment (LGG 40% vs. placebo 39%), with similar colonization prevalence for individual MDRO (Figure 1). There was no difference in any MDRO acquisition (LGG 27%, placebo 33%, OR 1.36, 95% CI 0.42–4.41) or any individual MDRO acquisition (Figure 2). There was also no difference in loss of any MDRO (LGG 18%, placebo 24%, OR 1.44, 95% CI 0.27–7.68) or any individual MDRO (Figure 2). CONCLUSION: LGG administration did not prevent acquisition of MDRO or accelerate loss of MDRO colonization. [Image: see text] [Image: see text] DISCLOSURES: All authors: No reported disclosures.