{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,25]],"date-time":"2026-09-25T23:19:03Z","timestamp":1790378343502,"version":"4.1.0"},"reference-count":20,"publisher":"Oxford University Press (OUP)","license":[{"start":{"date-parts":[[2026,8,4]],"date-time":"2026-08-04T00:00:00Z","timestamp":1785801600000},"content-version":"am","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000024","name":"Canadian Institutes of Health Research","doi-asserted-by":"publisher","award":["200950"],"award-info":[{"award-number":["200950"]}],"id":[{"id":"10.13039\/501100000024","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Physicians\u2019 Services Incorporated Foundation","id":[{"id":"https:\/\/ror.org\/0385yzn06","id-type":"ROR","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Patients with suspected bloodstream infection often receive broad-spectrum antibiotics with anaerobic activity in the absence of clinical indication for anaerobic coverage. Antianaerobic antibiotics have been linked to adverse clinical outcomes in other populations, potentially by depleting intestinal anaerobes.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We conducted a planned substudy of the multisite BALANCE randomized controlled trial of antibiotic duration for bloodstream infection to assess the impact of antianaerobic antibiotics (receipt from 3 days preindex culture to 7 days postindex) on mortality and gut microbiome composition with metagenomic sequencing in patients without clinical indication for anaerobic coverage who survived to 7 days postindex culture. The primary exposure was receipt of antianaerobic antibiotics from 3 days prior to the index culture to 7 days postindex culture.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Among the 2851 eligible patients included in our primary analysis, 2106 (74%) received antianaerobic antibiotics, and 745 (26%) did not. After balancing measured potential confounders through inverse probability of treatment weighting, antianaerobic antibiotics were associated with higher 90-day mortality (OR = 1.41, 95% CI 1.03\u20131.92, P = .03) and depletion of gut anaerobe relative abundance (fixed effect estimate = \u221216.59, 95% CI \u221230.67 to \u22122.52, P = .02). Increased duration of antianaerobic antibiotics was associated with greater mortality risk and additional gut anaerobe depletion.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Antianaerobic antibiotics are associated with increased mortality and gut microbiome disruption in patients with bloodstream infection. Minimizing exposure to antianaerobic antibiotics for bloodstream infection should be further explored in clinical trials as a potential treatment strategy to improve patient outcomes.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1093\/cid\/ciag460","type":"journal-article","created":{"date-parts":[[2026,8,1]],"date-time":"2026-08-01T12:07:05Z","timestamp":1785586025000},"source":"Crossref","is-referenced-by-count":1,"title":["Association of Antianaerobic Antibiotics With Mortality and the Gut Microbiome: A Substudy of the BALANCE Randomized Clinical Trial"],"prefix":"10.1093","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4530-6631","authenticated-orcid":false,"given":"Eric","family":"Armstrong","sequence":"first","affiliation":[{"name":"Toronto General Hospital Research Institute , University Health Network, Toronto, Ontario ,","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3712-4624","authenticated-orcid":false,"given":"Ruxandra","family":"Pinto","sequence":"additional","affiliation":[{"name":"Department of Medicine, Sunnybrook Health Sciences Centre , Toronto, Ontario ,","place":["Canada"]},{"name":"Institute of Health Policy, Management and Evaluation, University of Toronto , Toronto, Ontario ,","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0001-0300-8812","authenticated-orcid":false,"given":"Maria","family":"Kulikova","sequence":"additional","affiliation":[{"name":"Toronto General Hospital Research Institute , University Health Network, Toronto, Ontario ,","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-1817-5768","authenticated-orcid":false,"given":"Noelle 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,","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"David M","family":"Maslove","sequence":"additional","affiliation":[{"name":"Department of Critical Care Medicine, Queen's University , Kingston, Ontario ,","place":["Canada"]},{"name":"Department of Medicine, Queen's University , Kingston, Ontario ,","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"J Gordon","family":"Boyd","sequence":"additional","affiliation":[{"name":"Department of Critical Care Medicine, Queen's University , Kingston, Ontario ,","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2557-0897","authenticated-orcid":false,"given":"Gerald A","family":"Evans","sequence":"additional","affiliation":[{"name":"Division of Infectious Diseases, Department of Medicine, Queen's University , Kingston, Ontario 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Department of Medicine, Unity Health Toronto, St. Michael's Hospital , Toronto, Ontario ,","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7248-2350","authenticated-orcid":false,"given":"Jan O","family":"Friedrich","sequence":"additional","affiliation":[{"name":"Critical Care, Unity Health Toronto, St. Michael's Hospital, University of Toronto , Toronto, Ontario ,","place":["Canada"]},{"name":"Medicine, Unity Health Toronto, St. Michael's Hospital, University of Toronto , Toronto, Ontario ,","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1809-0505","authenticated-orcid":false,"given":"Jennifer L Y","family":"Tsang","sequence":"additional","affiliation":[{"name":"Niagara Health, Niagara Health Knowledge Institute , St. Catharine's, Ontario ,","place":["Canada"]},{"name":"Department of Medicine, McMaster University , Hamilton, Ontario 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