title: Emergence of multidrug resistance in ubiquitous and dominant Pseudomonas aeruginosa serogroup O:11. The Greek Pseudomonas Aeruginosa Study Group.
abstract: The serotypes of 88 nonreplicate nosocomial Pseudomonas aeruginosa isolates from 11 Greek hospitals were studied in relation to their antibiotic susceptibilities. Rates of resistance to beta-lactams, aminoglycosides, and quinolones ranged from 31 to 65%, except for those to ceftazidime (15%) and imipenem (21%). Four serotypes were dominant: O:12 (25% of isolates), O:1 (17%), O:11 (16%), and O:6 (10%). Multidrug resistance rates in the major serogroups O:12 (91%) and O:11 (79%) were higher than those in serogroups O:1 (40%) and O:6 (43%). Further typing with respect to pulsed-field gel electrophoresis patterns following XbaI digestion of genomic DNA discriminated the isolates into 74 types. Pulsed-field gel electrophoresis revealed that the ubiquitous O:12 group was genetically homogeneous, since 95% of strains belonged to two clusters of genotypic similarity, while the O:11 strains, present in 8 of the 11 hospitals, were distributed among five such clusters. Therefore, apart from the already reported O:12 multidrug-resistant European clone, an O:11 population, characterized by a serotype known to be dominant in the environment and the hospital in several parts of the world, but previously not associated with multidrug resistance to antibiotics, has progressed to a multidrug-resistant state.
authors.affiliation: Department of Microbiology, Medical School, National University of Athens, Greece.
authors.forename: P T
authors.initials: PT
authors.lastname: Tassios
authors.forename: V
authors.initials: V
authors.lastname: Gennimata
authors.forename: A N
authors.initials: AN
authors.lastname: Maniatis
authors.forename: C
authors.initials: C
authors.lastname: Fock
authors.forename: N J
authors.initials: NJ
authors.lastname: Legakis
mesh_terms: D016172:DNA Fingerprinting; D004269:DNA, Bacterial / Q000032:analysis; D004352:Drug Resistance, Microbial; D018432:Drug Resistance, Multiple; D011550:Pseudomonas aeruginosa / Q000145:classification / Q000187:drug effects*; D012703:Serotyping
chemical_list: D004269:DNA, Bacterial