{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,8]],"date-time":"2026-07-08T05:15:47Z","timestamp":1783487747267,"version":"3.55.0"},"reference-count":42,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2026,7,3]],"date-time":"2026-07-03T00:00:00Z","timestamp":1783036800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>Stenotrophomonas maltophilia is an emerging multidrug-resistant opportunistic pathogen in intensive care units (ICUs) and cystic fibrosis (CF), where biofilm formation may favor persistence, device-associated colonization\/infection, and clonal dissemination. This study compared biofilm formation, clonal relatedness, biofilm phenotypes, and motility in 37 ICU-associated and 42 CF-associated S. maltophilia isolates. Biofilm formation on polystyrene was quantified by crystal violet assay and expressed both as absolute biomass and as a growth-normalized Biofilm Index, calculated to account for differences in planktonic growth. Genetic diversity was assessed by pulsed-field gel electrophoresis, while swimming and twitching motility were evaluated using agar-based assays. ICU isolates showed a higher prevalence of biofilm formation, greater biofilm biomass, and higher growth-normalized Biofilm Index values than CF isolates. They also displayed lower genetic diversity and more frequent cross-transmission, supporting the circulation of selected hospital-associated lineages. Conversely, CF isolates showed greater heterogeneity and a more complex biofilm pattern, consistent with adaptation to a distinct chronic airway environment. Motility was not associated with biofilm formation, suggesting that the enhanced biofilm phenotype of ICU isolates is not explained by swimming or twitching alone. Overall, these findings support a setting-specific model in which enhanced biofilm-forming capacity may contribute to S. maltophilia ICU persistence and clonal dissemination, highlighting the need for targeted surveillance and careful device management.<\/jats:p>","DOI":"10.3390\/microorganisms14071471","type":"journal-article","created":{"date-parts":[[2026,7,3]],"date-time":"2026-07-03T14:33:06Z","timestamp":1783089186000},"page":"1471","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Enhanced Biofilm Formation by ICU-Associated Stenotrophomonas maltophilia Isolates: A Potential Contributor to Persistence and Clonal Dissemination"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5850-2810","authenticated-orcid":false,"given":"Giovanni","family":"Di Bonaventura","sequence":"first","affiliation":[{"name":"Department of Medical, Oral, and Biotechnological Sciences, \u201cG. D\u2019Annunzio\u201d University of Chieti-Pescara, 66100 Chieti, Italy"},{"name":"Center of Advanced Studies and Technology, \u201cG. D\u2019Annunzio\u201d University of Chieti-Pescara, 66100 Chieti, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Giovanni","family":"Gherardi","sequence":"additional","affiliation":[{"name":"Antibiotic Resistance and Special Pathogens Unit, Department of Infectious Diseases, Istituto Superiore di Sanit\u00e0, 00119 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0905-5003","authenticated-orcid":false,"given":"Martina","family":"Barchitta","sequence":"additional","affiliation":[{"name":"Department of Medical and Surgical Sciences and Advanced Technologies \u201cG.F. Ingrassia\u201d, University of Catania, 95123 Catania, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4405-8162","authenticated-orcid":false,"given":"Antonella","family":"Agodi","sequence":"additional","affiliation":[{"name":"Department of Medical and Surgical Sciences and Advanced Technologies \u201cG.F. Ingrassia\u201d, University of Catania, 95123 Catania, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6309-6981","authenticated-orcid":false,"given":"Arianna","family":"Pompilio","sequence":"additional","affiliation":[{"name":"Department of Medical, Oral, and Biotechnological Sciences, \u201cG. D\u2019Annunzio\u201d University of Chieti-Pescara, 66100 Chieti, Italy"},{"name":"Center of Advanced Studies and Technology, \u201cG. D\u2019Annunzio\u201d University of Chieti-Pescara, 66100 Chieti, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"330","DOI":"10.1016\/j.ijheh.2008.07.001","article-title":"Acquisition and spread of Acinetobacter baumannii and Stenotrophomonas maltophilia in intensive care patients","volume":"212","author":"Barchitta","year":"2009","journal-title":"Int. J. Hyg. Environ. Health"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1419","DOI":"10.1007\/s10096-011-1459-8","article-title":"Stenotrophomonas maltophilia in the respiratory tract of medical intensive care unit patients","volume":"31","author":"Saugel","year":"2012","journal-title":"Eur. J. Clin. Microbiol. Infect. 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