title: Fluoroquinolone resistance in penicillin-resistant Streptococcus pneumoniae clones, Spain.
abstract: Among 2,882 Streptococcus pneumoniae sent to the Spanish Reference Laboratory during 2002, 75 (2.6%) were ciprofloxacin-resistant. Resistance was associated with older patients (3.9% in adults and 7.2% in patients > or =65 years of age), with isolation from noninvasive sites (4.3% vs. 1.0%), and with penicillin and macrolide resistance. Among 14 low-level resistant (MIC 4-8 microg/mL) strains, 1 had a fluoroquinolone efflux phenotype, and 13 showed single ParC changes. The 61 high-level ciprofloxacin-resistant (MIC > or =16 microg/mL) strains showed either two or three changes at ParC, ParE, and GyrA. Resistance was acquired either by point mutation (70 strains) or by recombination with viridans streptococci (4 strains) at the topoisomerase II genes. Although 36 pulsed-field gel electrophoresis patterns were observed, 5 international multiresistant clones (Spain23F-1, Spain6B-2, Spain9V-3, Spain14-5 and Sweden15A-25) accounted for 35 (46.7%) of the ciprofloxacin-resistant strains. Continuous surveillance is needed to prevent the dissemination of these clones.
authors.affiliation: Unidad de Genética Bacteriana, Centro Nacional de Microbiología, Instituto de Salud Carlos III, 28220 Majadahonda, Madrid, Spain. agcampa@isciii.es
authors.forename: Adela G
authors.initials: AG
authors.lastname: de la Campa
authors.forename: Luz
authors.initials: L
authors.lastname: Balsalobre
authors.forename: Carmen
authors.initials: C
authors.lastname: Ardanuy
authors.forename: Asunción
authors.initials: A
authors.lastname: Fenoll
authors.forename: Emilio
authors.initials: E
authors.lastname: Pérez-Trallero
authors.forename: Josefina
authors.initials: J
authors.lastname: Liñares
mesh_terms: D000328:Adult; D001483:Base Sequence; D002648:Child; D027081:DNA Gyrase / Q000235:genetics; D027101:DNA Topoisomerase IV / Q000235:genetics; D004269:DNA, Bacterial / Q000032:analysis; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics; D024841:Fluoroquinolones / Q000494:pharmacology*; D006801:Humans; D008826:Microbial Sensitivity Tests; D017720:Molecular Epidemiology; D010403:Penicillin Resistance; D013030:Spain / Q000453:epidemiology; D013290:Streptococcal Infections / Q000453:epidemiology / Q000382:microbiology; D013296:Streptococcus pneumoniae / Q000187:drug effects* / Q000201:enzymology / Q000235:genetics
chemical_list: D004269:DNA, Bacterial; D024841:Fluoroquinolones; D027101:DNA Topoisomerase IV; D027081:DNA Gyrase