title: Antibiotic susceptibility patterns and clones of Pseudomonas aeruginosa in Swedish ICUs.
abstract: Pseudomonas aeruginosa is 1 of the bacteria most adaptive to anti-bacterial treatment. Previous studies have shown nosocomial spread and transmission of clonal strains of P. aeruginosa in European hospitals. In this study we investigated antibiotic susceptibility and clonality in 101 P. aeruginosa isolates from 88 patients admitted to 8 Swedish ICUs during 2002. We also compared phenotypes and genotypes of P. aeruginosa and carried out cluster analysis to determine if phenotypic data can be used for surveillance of clonal spread. All isolates were collected on clinical indication as part of the NPRS II study in Sweden and were subjected to AFLP analysis for genotyping. 68 isolates with unique genotypes were found. Phenotyping was performed using MIC values for 5 anti-pseudomonal agents. Almost 6% of the isolates were multi-drug resistant (MDR), and this figure rose to almost 8% when intermediate isolates were also included. We found probable clonal spread in 9 cases, but none of them was found to be an MDR strain. Phenotypical cluster analysis produced 40 clusters. Comparing partitions did not demonstrate any significant concordance between the typing methods. The conclusion of our study is that cross-transmission and clonal spread of MDR P. aeruginosa does not present a clinical problem in Swedish ICUs, but probable cross-transmission of non-MDR clones indicate a need for improved hygiene routines bedside. The phenotype clusters were not concordant with genotype clusters, and genotyping is still recommended for epidemiological tracking.
authors.affiliation: Division of Infectious Diseases, Department of Clinical and Experimental Medicine, Faculty of Health Sciences, Linköping University, Linköping, Sweden. marcus_e@telia.com
authors.forename: Marcus
authors.initials: M
authors.lastname: Erlandsson
authors.forename: Hans
authors.initials: H
authors.lastname: Gill
authors.forename: David
authors.initials: D
authors.lastname: Nordlinder
authors.forename: Christian G
authors.initials: CG
authors.lastname: Giske
authors.forename: Daniel
authors.initials: D
authors.lastname: Jonas
authors.forename: Lennart E
authors.initials: LE
authors.lastname: Nilsson
authors.forename: Sten
authors.initials: S
authors.lastname: Walther
authors.forename: Håkan
authors.initials: H
authors.lastname: Hanberger
mesh_terms: D054458:Amplified Fragment Length Polymorphism Analysis; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D015373:Bacterial Typing Techniques; D016000:Cluster Analysis; D003428:Cross Infection / Q000453:epidemiology / Q000382:microbiology; D004269:DNA, Bacterial / Q000235:genetics; D024901:Drug Resistance, Multiple, Bacterial; D005838:Genotype; D006801:Humans; D007362:Intensive Care Units; D008826:Microbial Sensitivity Tests; D010641:Phenotype; D011552:Pseudomonas Infections / Q000453:epidemiology* / Q000382:microbiology*; D011550:Pseudomonas aeruginosa / Q000145:classification* / Q000187:drug effects* / Q000302:isolation & purification; D013548:Sweden / Q000453:epidemiology
chemical_list: D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial