{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,1]],"date-time":"2026-10-01T09:04:38Z","timestamp":1790845478870,"version":"4.1.0"},"reference-count":36,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2020,8,3]],"date-time":"2020-08-03T00:00:00Z","timestamp":1596412800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Doctor Kasem Pangsrivongse Foundation","award":["001\/63"],"award-info":[{"award-number":["001\/63"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antibiotics"],"abstract":"<jats:p>Global infections with colistin-resistant Pseudomonas aeruginosa (CoR-PA) are increasing; there are currently very few studies focused on the antimicrobial susceptibility of CoR-PA isolates, and none from Thailand. Here, we investigated the impact of various antimicrobials, alone and in combination, via the in vitro testing of CoR-PA clinical isolates. Eighteen CoR-PA isolates were obtained from patients treated at Phramongkutklao Hospital from January 2010 through June 2019; these were classified into six different clonal types by using the enterobacterial repetitive intergenic consensus (ERIC)-PCR method, with a high prevalence of Group A (27.8%). The antimicrobial susceptibility was determined as the minimal inhibitory concentrations (MICs) using the epsilometer-test (E-test) method. The synergistic activities of six antimicrobial combinations were reported via the fractional-inhibitory-concentration index. All CoR-PA isolates were susceptible to amikacin, meropenem, and ceftolozane\/tazobactam, but only 5.56% were susceptible to imipenem. In vitro synergistic activities were detected for amikacin with aztreonam, piperacillin\/tazobactam, meropenem, and ceftazidime for 16.67%, 11.11%, 11.11%, and 5.55%, respectively. One CoR-PA isolate carried the blaVIM metallo-\u03b2-lactamase gene; none carried mcr-1 genes or detected plasmid-mediated AmpC \u03b2-lactamase or an overproduction of chromosomal AmpC \u03b2-lactamase. Seven CoR-PA isolates (38.89%) were capable of biofilm formation. In conclusion, CoR-PA isolates are highly susceptible to antimicrobials; the synergy observed in response to the various agents should be examined in a clinical setting.<\/jats:p>","DOI":"10.3390\/antibiotics9080475","type":"journal-article","created":{"date-parts":[[2020,8,3]],"date-time":"2020-08-03T03:16:46Z","timestamp":1596424606000},"page":"475","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Antimicrobials as Single and Combination Therapy for Colistin-Resistant Pseudomonas aeruginosa at a University Hospital in Thailand"],"prefix":"10.3390","volume":"9","author":[{"given":"Supanun","family":"Pungcharoenkijkul","sequence":"first","affiliation":[{"name":"College of Pharmacotherapy Thailand, Nontaburi 11000, Thailand"},{"name":"Department of Pharmacist, Nopparat Rajathanee Hospital, Bangkok 10230, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jantima","family":"Traipattanakul","sequence":"additional","affiliation":[{"name":"Division of Infectious Disease, Department of Medicine, Phramongkutklao Hospital, Bangkok 10400, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sudaluck","family":"Thunyaharn","sequence":"additional","affiliation":[{"name":"Faculty of Medical Technology, Nakhonratchasima College, Nakhon Ratchasima 30000, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9974-957X","authenticated-orcid":false,"given":"Wichai","family":"Santimaleeworagun","sequence":"additional","affiliation":[{"name":"Department of Pharmacy, Faculty of Pharmacy, Silpakorn University, Nakorn Pathom 73000, Thailand"},{"name":"Pharmaceutical Initiative for Resistant Bacteria and Infectious Disease Working Group (PIRBIG), Nakorn Pathom 73000, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,8,3]]},"reference":[{"key":"ref_1","first-page":"1167","article-title":"Infectious Due to Psudomonas, Burkholderia, and Stenotrophomonas Species","volume":"Volume 1","author":"Jameson","year":"2018","journal-title":"Harison\u2018s Prinsiples of Internal Medicine"},{"key":"ref_2","unstructured":"World Health Organization (2020, April 18). 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