{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T13:00:56Z","timestamp":1785416456439,"version":"3.56.0"},"reference-count":46,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2026,6,15]],"date-time":"2026-06-15T00:00:00Z","timestamp":1781481600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004587","name":"Instituto de Salud Carlos III","doi-asserted-by":"publisher","award":["PI25\/01285"],"award-info":[{"award-number":["PI25\/01285"]}],"id":[{"id":"10.13039\/501100004587","id-type":"DOI","asserted-by":"publisher"}]},{"award":["PI25\/01285"],"award-info":[{"award-number":["PI25\/01285"]}],"id":[{"id":"https:\/\/ror.org\/00ca2c886","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Medicina"],"abstract":"<jats:p>Background and Objectives: Surgical site infections (SSIs) remain common after elective colorectal surgery. This systematic review and meta-analysis evaluated whether adding oral antibiotic bowel preparation (OAB) to mechanical bowel preparation (MBP) reduces SSIs compared with MBP alone. Materials and Methods: PubMed, the Cochrane Library, Scopus, and ClinicalTrials.gov were searched for English-language randomized controlled trials published from January 2005 to January 2025. Eligible trials enrolled adults undergoing elective colorectal surgery and compared MBP+OAB versus MBP alone, with standard intravenous prophylaxis in both groups. The primary outcome was overall SSI; secondary outcomes were incisional SSI and organ-space SSI. Risk of bias was assessed with RoB 2, certainty with GRADE, and odds ratios (ORs) were pooled using DerSimonian\u2013Laird random-effects models. The protocol was prespecified but not prospectively registered. Results: Twelve trials including 4073 patients were included (MBP+OAB, n = 2069; MBP, n = 2004). MBP+OAB reduced overall SSI (OR 0.53, 95% CI 0.37\u20130.75; p &lt; 0.001; I2 = 62.5%; 95% prediction interval 0.17\u20131.66), incisional SSI (OR 0.52, 95% CI 0.34\u20130.80; p = 0.003; I2 = 57.5%), and organ-space SSI (OR 0.63, 95% CI 0.45\u20130.88; p = 0.007; I2 = 8.3%). The effect was preserved in metronidazole-containing regimens (OR 0.46, 95% CI 0.33\u20130.65), but this subgroup was exploratory. Excluding high-risk-of-bias studies supported the primary result. Publication-bias assessment was underpowered. Overall and organ-space SSI were moderate-certainty outcomes; incisional SSI was low-certainty, and anastomotic leak was very low-certainty. Conclusions: In contemporary elective colorectal surgery when MBP is used, adding preoperative OAB probably reduces SSIs. Findings do not establish whether OAB alone is sufficient or whether MBP is necessary; stewardship-relevant outcomes remain insufficiently reported. Funding was provided by ISCIII grant PI25\/01285.<\/jats:p>","DOI":"10.3390\/medicina62061161","type":"journal-article","created":{"date-parts":[[2026,6,15]],"date-time":"2026-06-15T15:00:48Z","timestamp":1781535648000},"page":"1161","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Adding Preoperative Oral Antibiotics to Mechanical Bowel Preparation Reduces Surgical Site Infections in Elective Colorectal Surgery: A Meta-Analysis of Randomized Controlled Trials"],"prefix":"10.3390","volume":"62","author":[{"given":"H\u00e9ctor","family":"Guadalajara","sequence":"first","affiliation":[{"name":"Department of Surgery, School of Medicine, Universidad Aut\u00f3noma de Madrid, 28029 Madrid, Spain"},{"name":"Department of General and Digestive Surgery, Hospital Universitario Fundaci\u00f3n Jim\u00e9nez D\u00edaz, Av. Reyes Cat\u00f3licos 2, 28040 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alicia","family":"Putan","sequence":"additional","affiliation":[{"name":"Department of Surgery, School of Medicine, Universidad Aut\u00f3noma de Madrid, 28029 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8142-1373","authenticated-orcid":false,"given":"Mariano","family":"Garc\u00eda Arranz","sequence":"additional","affiliation":[{"name":"Department of Surgery, School of Medicine, Universidad Aut\u00f3noma de Madrid, 28029 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9681-3203","authenticated-orcid":false,"given":"Miguel","family":"Le\u00f3n-Arellano","sequence":"additional","affiliation":[{"name":"Department of Surgery, School of Medicine, Universidad Aut\u00f3noma de Madrid, 28029 Madrid, Spain"},{"name":"Department of General and Digestive Surgery, Hospital Universitario Fundaci\u00f3n Jim\u00e9nez D\u00edaz, Av. Reyes Cat\u00f3licos 2, 28040 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9129-1020","authenticated-orcid":false,"given":"Raquel","family":"Sanz-Baro","sequence":"additional","affiliation":[{"name":"Department of Gynecology and Obstetrics, Hospital Universitario Fundaci\u00f3n Jim\u00e9nez D\u00edaz, Av. Reyes Cat\u00f3licos 2, 28040 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7964-1166","authenticated-orcid":false,"given":"Jose Manuel","family":"Ramirez","sequence":"additional","affiliation":[{"name":"Department of Surgery, School of Medicine, University of Zaragoza, 50009 Zaragoza, Spain"},{"name":"Department of Surgery, Aragon Institute for Health Research (IIS Aragon), 50009 Zaragoza, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9369-2338","authenticated-orcid":false,"given":"Dami\u00e1n","family":"Garc\u00eda-Olmo","sequence":"additional","affiliation":[{"name":"Department of Surgery, School of Medicine, Universidad Aut\u00f3noma de Madrid, 28029 Madrid, Spain"},{"name":"Department of General and Digestive Surgery, Hospital Universitario Fundaci\u00f3n Jim\u00e9nez D\u00edaz, Av. Reyes Cat\u00f3licos 2, 28040 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,6,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"374","DOI":"10.1007\/DCR.0b013e31819a5e45","article-title":"Surgical site infections in a \u201chigh outlier\u201d institution: Are colorectal surgeons to blame?","volume":"52","author":"Wick","year":"2009","journal-title":"Dis. Colon Rectum"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1055","DOI":"10.1007\/s00384-020-03557-3","article-title":"The influence of postoperative complications on long-term prognosis in patients with colorectal carcinoma","volume":"35","author":"Beck","year":"2020","journal-title":"Int. J. Color. 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