{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,3]],"date-time":"2026-08-03T19:45:31Z","timestamp":1785786331004,"version":"3.56.0"},"reference-count":26,"publisher":"American Society for Microbiology","issue":"2","license":[{"start":{"date-parts":[[2003,2,1]],"date-time":"2003-02-01T00:00:00Z","timestamp":1044057600000},"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":["J Clin Microbiol"],"published-print":{"date-parts":[[2003,2]]},"abstract":"<jats:title>ABSTRACT<\/jats:title>\n          <jats:p>\n            We tested 190\n            <jats:italic>Klebsiella pneumoniae<\/jats:italic>\n            bloodstream isolates recovered from 189 patients in 30 U.S. hospitals in 23 states to determine the occurrence of extended-spectrum \u03b2-lactamase (ESBL) and AmpC \u03b2-lactamase producers. Based on growth inhibition by clavulanic acid by disk and MIC test methods, 18 (9.5%) of the isolates produced ESBLs. Although the disk diffusion method with standard breakpoints identified 28 cefoxitin-nonsusceptible isolates, only 5 (18%) of these were confirmed as AmpC producers. Of two AmpC confirmatory tests, the three-dimensional extract test was easier to perform than was the double-disk approximation test using a novel inhibitor, Syn2190. Three of the five AmpC producers carried the\n            <jats:italic>bla<\/jats:italic>\n            <jats:sub>FOX-5<\/jats:sub>\n            gene, while the other two isolates harbored the\n            <jats:italic>bla<\/jats:italic>\n            <jats:sub>ACT-1<\/jats:sub>\n            gene. All AmpC genes were transferable. In vitro susceptibility testing with standard inocula showed that all five AmpC-producing strains were susceptible to cefepime, imipenem, and ertapenem but that with a high inoculum, more of these strains were susceptible to the carbapenems than to cefepime. All but 1 of 14 screen-positive AmpC nonproducers (and ESBL nonproducers) were susceptible to ceftriaxone and cefepime at the standard inoculum as were 6 of 6 isolates that were randomly selected and tested with a high inoculum. These results indicate that (i) a significant number of\n            <jats:italic>K. pneumoniae<\/jats:italic>\n            bloodstream isolates harbor ESBL or AmpC \u03b2-lactamases, (ii) confirmatory tests are necessary to identify true AmpC producers, and (iii) in vitro, carbapenems are active against AmpC-producing strains of\n            <jats:italic>K. pneumoniae<\/jats:italic>\n            .\n          <\/jats:p>","DOI":"10.1128\/jcm.41.2.772-777.2003","type":"journal-article","created":{"date-parts":[[2003,2,6]],"date-time":"2003-02-06T20:03:31Z","timestamp":1044561811000},"page":"772-777","update-policy":"https:\/\/doi.org\/10.1128\/asmj-crossmark-policy-page","source":"Crossref","is-referenced-by-count":60,"title":["Occurrence of Extended-Spectrum and AmpC Beta-Lactamases in Bloodstream Isolates of\n            <i>Klebsiella pneumoniae:<\/i>\n            Isolates Harbor Plasmid-Mediated FOX-5 and ACT-1 AmpC Beta-Lactamases"],"prefix":"10.1128","volume":"41","author":[{"given":"Philip E.","family":"Coudron","sequence":"first","affiliation":[{"name":"Pathology and Laboratory Medicine Service\/113"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nancy D.","family":"Hanson","sequence":"additional","affiliation":[{"name":"Department of Medical Microbiology and Immunology, Creighton University School of Medicine, Omaha, Nebraska 68178"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael W.","family":"Climo","sequence":"additional","affiliation":[{"name":"Department of Medicine, McGuire Veterans Affairs Medical Center, Richmond, Virginia 23249-0001"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"235","reference":[{"key":"e_1_3_2_2_2","doi-asserted-by":"publisher","DOI":"10.1128\/jcm.33.3.551-555.1995"},{"key":"e_1_3_2_3_2","doi-asserted-by":"publisher","DOI":"10.1128\/AAC.43.8.1924"},{"key":"e_1_3_2_4_2","doi-asserted-by":"publisher","DOI":"10.1128\/AAC.41.3.563"},{"key":"e_1_3_2_5_2","first-page":"1167","volume":"48","year":"2000","unstructured":"Centers for Disease Control and Prevention. 2000. Laboratory capacity to detect antimicrobial resistance, 1998. Morb. Mortal. Wkly. Rep.48:1167-1171.","journal-title":"Morb. Mortal. Wkly. Rep."},{"key":"e_1_3_2_6_2","doi-asserted-by":"publisher","DOI":"10.1128\/jcm.35.10.2593-2597.1997"},{"key":"e_1_3_2_7_2","doi-asserted-by":"publisher","DOI":"10.1128\/JCM.38.5.1791-1796.2000"},{"key":"e_1_3_2_8_2","doi-asserted-by":"publisher","DOI":"10.1001\/jama.284.24.3131"},{"key":"e_1_3_2_9_2","doi-asserted-by":"publisher","DOI":"10.1093\/jac\/47.2.207"},{"key":"e_1_3_2_10_2","doi-asserted-by":"publisher","DOI":"10.1093\/jac\/44.3.377"},{"key":"e_1_3_2_11_2","doi-asserted-by":"publisher","DOI":"10.1093\/clinids\/10.4.867"},{"key":"e_1_3_2_12_2","doi-asserted-by":"publisher","DOI":"10.1128\/AAC.45.10.2831-2837.2001"},{"key":"e_1_3_2_13_2","doi-asserted-by":"publisher","DOI":"10.1099\/00221287-88-1-169"},{"key":"e_1_3_2_14_2","unstructured":"National Committee for Clinical Laboratory Standards. 2000. Methods for dilution antimicrobial susceptibility tests for bacteria that grow aerobically. Approved standard M7-5. National Committee for Clinical Laboratory Standards Wayne Pa."},{"key":"e_1_3_2_15_2","unstructured":"National Committee for Clinical Laboratory Standards. 1994. Performance standards for antimicrobial susceptibility testing; fifth informational supplement. M100-S5. National Committee for Clinical Laboratory Standards Wayne Pa."},{"key":"e_1_3_2_16_2","unstructured":"National Committee for Clinical Laboratory Standards. 2002. Performance standards for antimicrobial susceptibility testing; twelfth informational supplement. M100-S12. National Committee for Clinical Laboratory Standards Wayne Pa."},{"key":"e_1_3_2_17_2","doi-asserted-by":"publisher","DOI":"10.1128\/AAC.43.8.1895"},{"key":"e_1_3_2_18_2","doi-asserted-by":"publisher","DOI":"10.1128\/JCM.39.6.2206-2212.2001"},{"key":"e_1_3_2_19_2","doi-asserted-by":"publisher","DOI":"10.1128\/JCM.40.6.2153-2162.2002"},{"key":"e_1_3_2_20_2","doi-asserted-by":"publisher","DOI":"10.1128\/AAC.46.1.1-11.2002"},{"key":"e_1_3_2_21_2","doi-asserted-by":"publisher","DOI":"10.1128\/AAC.45.11.3189-3194.2001"},{"key":"e_1_3_2_22_2","doi-asserted-by":"publisher","DOI":"10.1093\/jac\/49.3.557"},{"key":"e_1_3_2_23_2","doi-asserted-by":"publisher","DOI":"10.1128\/JCM.39.8.2864-2872.2001"},{"key":"e_1_3_2_24_2","first-page":"1393","volume":"36","year":"1992","unstructured":"Thomson, K. S., and C. C. Sanders. 1992. Detection of extended-spectrum \u03b2-lactamases in members of the family Enterobacteriaceae: comparison of the double-disk and three-dimensional tests. Antimicrob. Agents. Chemother.36:1393-1400.","journal-title":"Antimicrob. Agents. Chemother."},{"key":"e_1_3_2_25_2","doi-asserted-by":"publisher","DOI":"10.1128\/AAC.45.12.3548-3554.2001"},{"key":"e_1_3_2_26_2","doi-asserted-by":"publisher","DOI":"10.1128\/JCM.38.4.1495-1497.2000"},{"key":"e_1_3_2_27_2","doi-asserted-by":"publisher","DOI":"10.1086\/324742"}],"container-title":["Journal of Clinical Microbiology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/journals.asm.org\/doi\/pdf\/10.1128\/JCM.41.2.772-777.2003","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.asm.org\/doi\/pdf\/10.1128\/JCM.41.2.772-777.2003","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2022,3,5]],"date-time":"2022-03-05T02:18:59Z","timestamp":1646446739000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.asm.org\/doi\/10.1128\/JCM.41.2.772-777.2003"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2003,2]]},"references-count":26,"journal-issue":{"issue":"2","published-print":{"date-parts":[[2003,2]]}},"alternative-id":["10.1128\/JCM.41.2.772-777.2003"],"URL":"https:\/\/doi.org\/10.1128\/jcm.41.2.772-777.2003","relation":{},"ISSN":["0095-1137","1098-660X"],"issn-type":[{"value":"0095-1137","type":"print"},{"value":"1098-660X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2003,2]]},"assertion":[{"value":"2002-08-12","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2002-11-12","order":1,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2003-02-01","order":2,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}