{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T19:15:34Z","timestamp":1792782934312,"version":"4.5.0"},"reference-count":20,"publisher":"Springer Science and Business Media LLC","issue":"9","license":[{"start":{"date-parts":[[2026,6,24]],"date-time":"2026-06-24T00:00:00Z","timestamp":1782259200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2026,6,24]],"date-time":"2026-06-24T00:00:00Z","timestamp":1782259200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"name":"Eskisehir Osmangazi University","id":[{"id":"https:\/\/ror.org\/01dzjez04","id-type":"ROR","asserted-by":"crossref"}]}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Eur J Clin Microbiol Infect Dis"],"published-print":{"date-parts":[[2026,9]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Purpose<\/jats:title>\n                    <jats:p>\n                      Carbapenem-resistant\n                      <jats:italic>Pseudomonas aeruginosa<\/jats:italic>\n                      (CRPA) has been classified by the World Health Organization as one of the most alarming antimicrobial-resistant microorganisms. Despite the availability of newer therapeutic options, polymyxins remain important last-resort agents for the treatment of CRPA infections in many settings. With the extended use of polymyxins in the treatment of extensively drug-resistant bacterial infections, both colistin resistance rates, colistin heteroresistance (CHR) rates and antibiotic treatment failures have risen. In this study, we aimed to: (i) determine the prevalence of CHR in\n                      <jats:italic>P. aeruginosa<\/jats:italic>\n                      bloodstream isolates, (ii) compare the accuracy of the antibiotic gradient test (GT) with the population analysis profiling (PAP) method, and (iii) identify clinical risk factors for CHR.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>\n                      CHR was investigated among 70 colistin-susceptible\n                      <jats:italic>P. aeruginosa<\/jats:italic>\n                      strains isolated from blood cultures using PAP and GT methods. Clinical and demographical data were retrospectively reviewed, and risk factors for CHR were analyzed using logistic regression.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      We detected a remarkably high prevalence of CHR (61.4%) among colistin-susceptible\n                      <jats:italic>P. aeruginosa<\/jats:italic>\n                      bloodstream isolates. The gradient test failed to detect any of the heteroresistant strains. Our analysis revealed that age\u2009\u2265\u200960 years, lack of recent hospitalization, and a colistin MIC of 1\u00a0mg\/L, compared with 2\u00a0mg\/L, were independently associated with an increased risk of CHR. CHR was not significantly associated with 30-day or 90-day mortality.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Despite the microbiological importance of heteroresistance, the clinical impacts and underlying mechanisms of this phenotype remain to be elucidated.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1007\/s10096-026-05576-4","type":"journal-article","created":{"date-parts":[[2026,6,24]],"date-time":"2026-06-24T12:47:33Z","timestamp":1782305253000},"page":"2881-2890","update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["High prevalence of colistin heteroresistance in Pseudomonas aeruginosa bloodstream isolates and associated clinical factors"],"prefix":"10.1007","volume":"45","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6574-7995","authenticated-orcid":false,"given":"Ekin","family":"K\u0131rba\u015f","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0462-9765","authenticated-orcid":false,"given":"Muhammed Cihan","family":"I\u015f\u0131k","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7093-2722","authenticated-orcid":false,"given":"Rashad","family":"Ismayilov","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1184-4711","authenticated-orcid":false,"given":"Serhat","family":"\u00dcnal","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4015-4210","authenticated-orcid":false,"given":"Banu","family":"Sancak","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2026,6,24]]},"reference":[{"key":"5576_CR1","volume-title":"WHO Bacterial Priority Pathogens List, 2024: Bacterial pathogens of public health importance to guide research, development and strategies to prevent and control antimicrobial resistance","author":"World Health Organization","year":"2024","unstructured":"World Health Organization (2024) WHO Bacterial Priority Pathogens List, 2024: Bacterial pathogens of public health importance to guide research, development and strategies to prevent and control antimicrobial resistance. 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The requirement for informed consent was waived because of the retrospective methodology.","order":1,"name":"Ethics","label":"Ethics approval","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"The authors declare no competing interests.","order":2,"name":"Ethics","label":"Competing interests","group":{"name":"EthicsHeading","label":"Declarations"}}]}}