Enteral nutrition, gut microbiota alterations, and SIBO-related outcomes in critically ill patients: a systematic review
DOI: 10.30867/gikes.v7i2.3286Abstract
Background: Critically ill patients frequently develop gut dysbiosis, characterized by reduced microbial diversity and increased colonization by opportunistic pathogens. These alterations may contribute to gastrointestinal dysfunction and are associated with small intestinal bacterial overgrowth (SIBO)-related outcomes. Enteral nutrition is a key nutritional strategy for critically ill patients and may influence gut microbiota composition; however, its role in modulating the microbiota and its implications for SIBO-related outcomes remain unclear.
Objectives: This systematic review aimed to synthesize evidence on the relationship between enteral nutrition and gut microbiota modulation in critically ill adults and explore its potential implications for SIBO-related gastrointestinal outcomes.
Methods: A systematic review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA 2020) guidelines and registered in the PROSPERO database (CRD420261384432). Literature searches were performed in PubMed and Google Scholar for studies published between 2020 and 2026. Observational studies and randomized controlled trials involving critically ill patients receiving enteral nutrition, with outcomes related to the gut microbiota, gastrointestinal function, or SIBO were included. Data were extracted and synthesized narratively and thematically.
Results: Seven studies were included in the meta-analysis. Evidence from studies directly assessing microbiota has demonstrated reduced microbial diversity and increased abundance of opportunistic pathogens during critical illness. Studies evaluating fiber- or prebiotic-containing enteral formulas suggested potential increases in short-chain fatty acid (SCFA)-producing bacteria, although the findings remained inconsistent and were influenced by antibiotic exposure and clinical severity. Only one of the included studies directly evaluated SIBO.
Conclusion: Enteral nutrition may influence the gut microbiota composition in critically ill patients; however, direct evidence regarding SIBO remains limited. Further prospective studies using standardized microbiota and SIBO assessment methods are needed before the clinical implications for nutritional practice can be more clearly established.Keywords
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Blaser, A. R., Starkopf, J., Alhazzani, W., Berger, M. M., Casaer, M. P., Deane, A. M., & ESICM Working Group. (2021). Early enteral nutrition in critically ill patients: ESICM clinical practice guidelines. Intensive Care Medicine, 47(12), 1326–1342. https://doi.org/10.1007/s00134-021-06570-y
Freedberg, D. E., Messina, M., Lynch, E., Tess, M., Miracle, E., Chong, D. H., Abrams, J. A., & colleagues. (2020). Impact of fiber-based enteral nutrition on the gut microbiome of ICU patients receiving broad-spectrum antibiotics: A randomized pilot trial. Critical Care Explorations, 2(6), e0135. https://doi.org/10.1097/CCE.0000000000000135
Haak, B. W., & Wiersinga, W. J. (2021). The role of the gut microbiota in sepsis. The Lancet Gastroenterology & Hepatology, 6(2), 135–143. https://doi.org/10.1016/S2468-1253(20)30327-4
Karakosta, A., Bousvaros, K., Margaritis, A., Moschovi, P., Mousafiri, O., Fousekis, F., et al. (2024). High prevalence of small intestinal bacterial overgrowth syndrome in ICU patients: An observational study. Journal of Intensive Care Medicine, 39(1), 69–76. https://doi.org/10.1177/08850666231190284
McClave, S. A., Taylor, B. E., Martindale, R. G., Warren, M. M., Johnson, D. R., Braunschweig, C., et al. (2016). Guidelines for the provision and assessment of nutrition support therapy in the adult critically ill patient. JPEN Journal of Parenteral and Enteral Nutrition, 40(2), 159–211. https://doi.org/10.1177/0148607115621863
Ni, Y., Zhang, L., Chen, Y., Wang, H., Liu, X., Zhao, J., et al. (2022). Alterations of gut microbiota in critically ill patients with enteral nutrition-associated diarrhea. Frontiers in Microbiology, 13, 845523. https://doi.org/10.3389/fmicb.2022.845523
Park, H. J., Ahn, Y. H., Lee, H. Y., Lee, S. M., & Lee, J. (2025). The impact of enteral feeding intolerance on the prognosis of patients with septic shock in South Korea. Acute and Critical Care, 40(2), 304–312. https://doi.org/10.4266/acc.000700
Pimentel, M., Saad, R. J., Long, M. D., & Rao, S. S. C. (2020). ACG clinical guideline: Small intestinal bacterial overgrowth. The American Journal of Gastroenterology, 115(2), 165–178. https://doi.org/10.14309/ajg.0000000000000501
Quigley, E. M. M. (2020). The spectrum of small intestinal bacterial overgrowth (SIBO). Current Gastroenterology Reports, 22(1), Article 3. https://doi.org/10.1007/s11894-019-0747-8
Quigley, E. M. M., & Murray, J. A. (2021). Small intestinal bacterial overgrowth: Roles of antibiotics, prebiotics, and probiotics. Gastroenterology Clinics of North America, 50(2), 391–405. https://doi.org/10.1016/j.gtc.2021.02.005
Reintam Blaser, A., Malbrain, M. L. N. G., Starkopf, J., Fruhwald, S., Jakob, S. M., De Waele, J., et al. (2020). Gastrointestinal function in intensive care patients: Terminology, definitions and management. Intensive Care Medicine, 46(2), 269–284. https://doi.org/10.1007/s00134-019-05862-3
Serbanescu, M. A., Wright, M. C., Elebasy, M., Shi, P., Arnold, J. W., Haines, K. L., et al. (2025). Impact of fiber-containing enteral nutrition on microbial community dynamics in critically ill trauma patients: A pilot randomized trial. BMC Medicine, 23(1). https://doi.org/10.1186/s12916-025-04511-2
Singer, P., Blaser, A. R., Berger, M. M., Alhazzani, W., Calder, P. C., Casaer, M. P., et al. (2019). ESPEN guideline on clinical nutrition in the intensive care unit. Clinical Nutrition, 38(1), 48–79. https://doi.org/10.1016/j.clnu.2018.08.037
Wozniak, H., Beckmann, T. S., Fröhlich, L., Soccorsi, T., Le Terrier, C., de Watteville, A., et al. (2022). The central and biodynamic role of gut microbiota in critically ill patients. Critical Care, 26, 250. https://doi.org/10.1186/s13054-022-04127-5
Wozniak, H., Gaia, N., Lazarevic, V., Le Terrier, C., Beckmann, T. S., Balzani, E., et al. (2024). Early reduction in gut microbiota diversity in critically ill patients is associated with mortality. Annals of Intensive Care, 14, 174. https://doi.org/10.1186/s13613-024-01407-x
Xiao, Y., & Xu, L. (2023). Prevalence and risk factors of enteral feeding intolerance in critically ill patients and the effectiveness of preventive treatments: A prospective study. Saudi Journal of Medicine & Medical Sciences, 11(2), 135–142. https://doi.org/10.4103/sjmms.sjmms_384_22
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