title: Epidemiology and clinical outcomes of patients with multiresistant Pseudomonas aeruginosa.
abstract: We conducted a case-series study of multiresistant Pseudomonas aeruginosa in patients who did not have cystic fibrosis. Patient characteristics, antibiotic exposures, time course of emergence of resistance, and clinical outcomes were examined. Twenty-two patients were identified from whom P. aeruginosa resistant to ciprofloxacin, imipenem, ceftazidime, and piperacillin was isolated. Nineteen (86%) had clinical infection. Patients received prolonged courses of antipseudomonal antibiotics before isolation of multiresistant P. aeruginosa. Nine of 11 patients with soft-tissue infection exhibited resolution of clinical infection but usually required surgical removal of infected tissue with or without revascularization. Overall, three patients died. In two instances in which multiple isolates with different susceptibility profiles from the same patient were available, pulsed-field gel electrophoresis profiles of serial isolates were indistinguishable or closely related. This study illustrates that multiresistant P. aeruginosa emerges in a stepwise manner after exposure to antipseudomonal antibiotics and results in adverse outcomes.
authors.affiliation: Department of Pathology, Beth Israel Deaconess Medical Center, and Harvard Medical School, Boston, Massachusetts 02215, USA. aharris@caregroup.harvard.edu
authors.forename: A
authors.initials: A
authors.lastname: Harris
authors.forename: C
authors.initials: C
authors.lastname: Torres-Viera
authors.forename: L
authors.initials: L
authors.lastname: Venkataraman
authors.forename: P
authors.initials: P
authors.lastname: DeGirolami
authors.forename: M
authors.initials: M
authors.lastname: Samore
authors.forename: Y
authors.initials: Y
authors.lastname: Carmeli
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D003131:Combined Modality Therapy; D018432:Drug Resistance, Multiple; D016521:Electrophoresis, Gel, Pulsed-Field; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011552:Pseudomonas Infections / Q000188:drug therapy* / Q000382:microbiology / Q000401:mortality / Q000601:surgery; D011550:Pseudomonas aeruginosa / Q000145:classification* / Q000187:drug effects / Q000302:isolation & purification; D012189:Retrospective Studies; D012703:Serotyping
chemical_list: D000900:Anti-Bacterial Agents