title: Occurrence of multidrug resistance to oral antibiotics among Escherichia coli urine isolates from outpatient departments in Germany: extended-spectrum β-lactamases and the role of fosfomycin.
abstract: The in vitro activities of fosfomycin and seven other antibiotics commonly used for oral treatment of urinary tract infections (UTIs) were evaluated for 499 Escherichia coli isolated from urine samples during a nationwide laboratory-based surveillance study in 2010. Overall, the highest resistance rates were found for amoxicillin (42.9%), followed by amoxicillin/clavulanic acid (32.7%), trimethoprim/sulfamethoxazole (SXT) (30.9%), ciprofloxacin (19.8%), cefuroxime (10.0%), cefpodoxime (8.6%) and cefixime (8.2%). One-half of the isolates (n=252; 50.5%) were fully susceptible to the eight drugs, whilst only 6 strains (1.2%) were resistant to fosfomycin. Combined resistance to amoxicillin, cefuroxime, ciprofloxacin and SXT was detected in 29 isolates (5.8%). Moreover, 40 isolates (8.0%) produced an extended-spectrum β-lactamase (ESBL), including CTX-M-type ESBLs detected in 39/40 isolates (97.5%) and a TEM-52 ESBL in 1 strain (2.5%). The predominant CTX-M-type ESBL was CTX-M-15 (27/39; 69.2%). Of the 27 CTX-M-15 producers, 19 (70.4%) belonged to the clonal lineage E. coli O25b-ST131. All but one ESBL-producing strains were fosfomycin-susceptible. In view of the emergence of multidrug resistance to standard oral antibiotics, these data support that oral fosfomycin (trometamol salt) may represent a valuable option in the treatment of uncomplicated UTIs.
authors.affiliation: Antiinfectives Intelligence GmbH, Rheinbach, Germany; Rhine University of Applied Sciences, Cologne, Germany. Electronic address: michael.kresken@antiinfectives-intelligence.de.
authors.forename: Michael
authors.initials: M
authors.lastname: Kresken
authors.affiliation: Robert Koch Institute, FG13 Nosocomial Pathogens and Antibiotic Resistance, Wernigerode, Germany.
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Pfeifer
authors.affiliation: Institute of Pharmacology and Clinical Pharmacology, Heinrich-Heine-University, Düsseldorf, Germany.
authors.forename: Dieter
authors.initials: D
authors.lastname: Hafner
authors.affiliation: Antiinfectives Intelligence GmbH, Rheinbach, Germany.
authors.forename: Rebecca
authors.initials: R
authors.lastname: Wresch
authors.affiliation: Antiinfectives Intelligence GmbH, Rheinbach, Germany.
authors.forename: Barbara
authors.initials: B
authors.lastname: Körber-Irrgang
mesh_terms: D000284:Administration, Oral; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000553:Ambulatory Care; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000494:pharmacology*; D002648:Child; D002675:Child, Preschool; D017714:Community-Acquired Infections / Q000382:microbiology; D024901:Drug Resistance, Multiple, Bacterial; D004926:Escherichia coli / Q000145:classification / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D004927:Escherichia coli Infections / Q000382:microbiology*; D005260:Female; D005838:Genotype; D005858:Germany; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D058889:Molecular Typing; D014552:Urinary Tract Infections / Q000382:microbiology*; D055815:Young Adult; D001618:beta-Lactamases / Q000145:classification / Q000235:genetics
chemical_list: D000900:Anti-Bacterial Agents; D001618:beta-Lactamases
keywords: CTX-M-15; Community-acquired; Outpatients; ST131; Uropathogen