Antimicrobial resistance in community and nosocomial Escherichia coli urinary tract isolates, London 2005-2006.
BACKGROUND
Escherichia coli is the commonest cause of community and nosocomial urinary tract infection (UTI). Antibiotic treatment is usually empirical relying on susceptibility data from local surveillance studies. We therefore set out to determine levels of resistance to 8 commonly used antimicrobial agents amongst all urinary isolates obtained over a 12 month period.


METHODS
Antimicrobial susceptibility to ampicillin, amoxicillin/clavulanate, cefalexin, ciprofloxacin, gentamicin, nitrofurantoin, trimethoprim and cefpodoxime was determined for 11,865 E. coli urinary isolates obtained from community and hospitalised patients in East London.


RESULTS
Nitrofurantoin was the most active agent (94% susceptible), followed by gentamicin and cefpodoxime. High rates of resistance to ampicillin (55%) and trimethoprim (40%), often in combination were observed in both sets of isolates. Although isolates exhibiting resistance to multiple drug classes were rare, resistance to cefpodoxime, indicative of Extended spectrum beta-lactamase production, was observed in 5.7% of community and 21.6% of nosocomial isolates.


CONCLUSIONS
With the exception of nitrofurantoin, resistance to agents commonly used as empirical oral treatments for UTI was extremely high. Levels of resistance to trimethoprim and ampicillin render them unsuitable for empirical use. Continued surveillance and investigation of other oral agents for treatment of UTI in the community is required.
Centre for Infectious Disease, Institute of Cell and Molecular Science, Barts and The London, Queen Mary's School of Medicine and Dentistry, London, UK. d.c.bean@qmul.ac.uk
David C
DC
Bean
Daniel
D
Krahe
David W
DW
Wareham
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002648:Child; D002675:Child, Preschool; D017714:Community-Acquired Infections / Q000382:microbiology*; D003428:Cross Infection / Q000382:microbiology*; D024881:Drug Resistance, Bacterial; D024901:Drug Resistance, Multiple, Bacterial; D004926:Escherichia coli / Q000187:drug effects* / Q000302:isolation & purification; D004927:Escherichia coli Infections / Q000382:microbiology*; D005260:Female; D006801:Humans; D007223:Infant; D008131:London; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D014552:Urinary Tract Infections / Q000382:microbiology*
D000900:Anti-Bacterial Agents