{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,7]],"date-time":"2026-10-07T00:43:20Z","timestamp":1791333800082,"version":"4.3.1"},"reference-count":19,"publisher":"American Society for Microbiology","issue":"4","license":[{"start":{"date-parts":[[2025,7,1]],"date-time":"2025-07-01T00:00:00Z","timestamp":1751328000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2025,7,1]],"date-time":"2025-07-01T00:00:00Z","timestamp":1751328000000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/journals.asm.org\/non-commercial-tdm-license"}],"content-domain":{"domain":["journals.asm.org"],"crossmark-restriction":true},"short-container-title":["ASM Case Rep"],"published-print":{"date-parts":[[2025,7]]},"abstract":"ABSTRACT<\/jats:title>\n \n \n \n Background<\/jats:title>\n \n Kluyvera<\/jats:italic>\n are gastrointestinal commensals and emerging opportunistic pathogens.\n Kluyvera<\/jats:italic>\n are considered intrinsically resistant to ampicillin and early generation cephalosporins due to chromosomal \u03b2-lactamase encoding\n bla<\/jats:italic>\n KLU<\/jats:sub>\n genes, which are the proposed ancestors of modern CTX-M enzymes.\n <\/jats:p>\n <\/jats:sec>\n \n Case Summary<\/jats:title>\n \n Here, we present a case of bacteremia and septic shock in a 61-year-old patient with uncontrolled type 2 diabetes caused by the rare species,\n Kluyvera intermedia<\/jats:italic>\n . It was misidentified as \u201c\n Enterobacter<\/jats:italic>\n (non-\n cloacae<\/jats:italic>\n complex)\u201d by the ePlex blood culture molecular identification panel. The\n K. intermedia<\/jats:italic>\n displayed atypical susceptibility to all \u03b2-lactams that diverge from previous clinical case reports on\n Kluyvera<\/jats:italic>\n . The patient was successfully treated with piperacillin-tazobactam and surgical source control. Only one clinical case of\n K. intermedia<\/jats:italic>\n infection has been reported before. We identified three other cases at our institution from 2023 and 2024, including two severe infections. Analysis of 162 publicly available\n Kluyvera<\/jats:italic>\n genomes on NCBI revealed that chromosomal\n bla<\/jats:italic>\n KLU<\/jats:sub>\n genes are not uniformly present in all\n Kluyvera<\/jats:italic>\n species. Strikingly, chromosomal\n bla<\/jats:italic>\n KLU<\/jats:sub>\n genes are present in 0% of\n K. intermedia<\/jats:italic>\n genomes; 100% of\n Kluyvera ascorbata, Kluyvera cryocrescens,<\/jats:italic>\n and\n Kluyvera sichuanensis<\/jats:italic>\n genomes; and 50% of other\n Kluyvera<\/jats:italic>\n species genomes. There is also extensive diversity in the prevalence of plasmid-mediated extended-spectrum \u03b2-lactamases and carbapenemases across\n Kluyvera<\/jats:italic>\n species.\n <\/jats:p>\n <\/jats:sec>\n \n Conclusion<\/jats:title>\n \n This case highlights clinically relevant, species-specific genomic variation in\n Kluyvera<\/jats:italic>\n that impacts antimicrobial susceptibility and treatment.\n K. intermedia<\/jats:italic>\n has a distinct genomic landscape of antimicrobial resistance than other\n Kluyvera<\/jats:italic>\n species, suggesting that the origin of CTX-M enzymes may still be unknown. This case underscores the importance of utilizing culture-based identification and phenotypic susceptibility testing to guide the treatment of\n Kluyvera<\/jats:italic>\n infections.\n <\/jats:p>\n <\/jats:sec>\n <\/jats:sec>","DOI":"10.1128\/asmcr.00047-25","type":"journal-article","created":{"date-parts":[[2025,6,12]],"date-time":"2025-06-12T09:01:01Z","timestamp":1749718861000},"update-policy":"https:\/\/doi.org\/10.1128\/asmj-crossmark-policy-page","source":"Crossref","is-referenced-by-count":3,"title":["Bacteremia due to a rare opportunistic pathogen,\n Kluyvera intermedia<\/i>\n , with atypical antimicrobial susceptibility in the absence of \u03b2-lactamases"],"prefix":"10.1128","volume":"1","author":[{"given":"Tevan","family":"Luong","sequence":"first","affiliation":[{"id":[{"id":"https:\/\/ror.org\/04gyf1771","id-type":"ROR","asserted-by":"publisher"}],"name":"School of Medicine, University of California, Irvine","place":["Irvine, USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anatasia","family":"Weiland","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/04gyf1771","id-type":"ROR","asserted-by":"publisher"}],"name":"Division of Infectious Diseases, Department of Medicine, School of Medicine, University of California, Irvine","place":["Irvine, USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lanny","family":"Hsieh","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/04gyf1771","id-type":"ROR","asserted-by":"publisher"}],"name":"Division of Infectious Diseases, Department of Medicine, School of Medicine, University of California, Irvine","place":["Irvine, USA"]},{"id":[{"id":"https:\/\/ror.org\/04gyf1771","id-type":"ROR","asserted-by":"publisher"}],"name":"Division of Hospital Medicine and Palliative Medicine, School of Medicine, University of California, Irvine","place":["Irvine, USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0489-0712","authenticated-orcid":true,"given":"Ayesha","family":"Khan","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/04gyf1771","id-type":"ROR","asserted-by":"publisher"}],"name":"Division of Clinical Microbiology, Department of Pathology and Laboratory Medicine, School of Medicine, University of California, Irvine","place":["Irvine, USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"235","reference":[{"key":"e_1_3_3_2_2","doi-asserted-by":"publisher","DOI":"10.1086\/322686"},{"key":"e_1_3_3_3_2","doi-asserted-by":"publisher","DOI":"10.1128\/spectrum.04054-23"},{"key":"e_1_3_3_4_2","doi-asserted-by":"publisher","DOI":"10.1128\/jcm.13.5.919-933.1981"},{"key":"e_1_3_3_5_2","doi-asserted-by":"publisher","DOI":"10.3390\/microorganisms11122836"},{"key":"e_1_3_3_6_2","unstructured":"CDC. 2019. 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Department of Health and Human Services"},{"key":"e_1_3_3_7_2","doi-asserted-by":"publisher","DOI":"10.1128\/spectrum.00542-24"},{"key":"e_1_3_3_8_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.idcr.2019.e00498"},{"key":"e_1_3_3_9_2","doi-asserted-by":"publisher","DOI":"10.1093\/jac\/dky304"},{"key":"e_1_3_3_10_2","doi-asserted-by":"publisher","DOI":"10.1128\/AAC.01238-18"},{"key":"e_1_3_3_11_2","doi-asserted-by":"publisher","DOI":"10.3389\/fmicb.2021.727435"},{"key":"e_1_3_3_12_2","doi-asserted-by":"publisher","DOI":"10.1128\/AAC.46.12.4041-4042.2002"},{"key":"e_1_3_3_13_2","doi-asserted-by":"publisher","DOI":"10.1016\/S2666-5247(23)00390-7"},{"key":"e_1_3_3_14_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.idcr.2023.e01765"},{"key":"e_1_3_3_15_2","doi-asserted-by":"publisher","DOI":"10.3389\/fmicb.2020.579306"},{"key":"e_1_3_3_16_2","doi-asserted-by":"publisher","DOI":"10.1373\/clinchem.2014.221770"},{"key":"e_1_3_3_17_2","doi-asserted-by":"publisher","DOI":"10.3390\/molecules25204775"},{"key":"e_1_3_3_18_2","doi-asserted-by":"publisher","DOI":"10.3389\/fmicb.2012.00110"},{"key":"e_1_3_3_19_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.jgar.2017.05.007"},{"key":"e_1_3_3_20_2","doi-asserted-by":"publisher","DOI":"10.1128\/AAC.02424-20"}],"container-title":["ASM Case Reports"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/journals.asm.org\/doi\/pdf\/10.1128\/asmcr.00047-25","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.asm.org\/doi\/pdf\/10.1128\/asmcr.00047-25","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,9,9]],"date-time":"2025-09-09T17:29:17Z","timestamp":1757438957000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.asm.org\/doi\/10.1128\/asmcr.00047-25"}},"subtitle":[],"editor":[{"given":"Ritu","family":"Banerjee","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"editor"}]}],"short-title":[],"issued":{"date-parts":[[2025,7]]},"references-count":19,"journal-issue":{"issue":"4","published-print":{"date-parts":[[2025,7]]}},"alternative-id":["10.1128\/asmcr.00047-25"],"URL":"https:\/\/doi.org\/10.1128\/asmcr.00047-25","relation":{},"ISSN":["2996-2684"],"issn-type":[{"value":"2996-2684","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,7]]},"assertion":[{"value":"2025-03-07","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2025-05-20","order":2,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2025-06-12","order":3,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}],"article-number":"e00047-25"}}