Extended-spectrum beta-lactamase-producing Enterobacteriaceae in hospital urinary tract infections: incidence and antibiotic susceptibility profile over 9 years.
PURPOSE
Extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae are an increasing concern regarding antibiotic resistance and their potential to cause serious infections which are difficult to treat. The purpose of this surveillance programme was to assess the incidence of ESBL in adults amongst urinary isolates, identify risk factors, and detail the antibiotic susceptibility profile in order to guide empirical treatment.


METHODS
From 2006 to 2014, we reviewed 21,414 positive urine cultures for E. coli and Klebsiella sp. from a University hospital in the UK and found 1420 ESBL-positive specimens. Susceptibility testing was performed by British Society of Antimicrobial Chemotherapy disc diffusion testing. ESBL screening was performed on samples resistant to cefpodoxime and confirmed by double disc diffusion (Oxoid Ltd, Basingstoke, UK). Patient gender, age, inpatient status, and catheterisation were assessed as risk factors.


RESULTS
ESBL production amongst E. coli urine cultures increased 44 %, from 4.6 to 6.6 % of all E. coli isolates. ESBL-positive organisms were associated with increases in drug resistance, particularly amongst fluoroquinolones, trimethoprim, and cephalexin. Multidrug resistance was a feature with 75 % of ESBL+ Klebsiella sp.-resistant ≥6 antibiotic classes. ESBL producers remained largely susceptible to carbapenems. Male gender, urinary catheterisation, inpatient status, and increasing age were identified as risk factors for ESBL infection or colonisation.


CONCLUSION
We demonstrate that the incidence of ESBL-producing E. coli in urine cultures is increasing and that such isolates are multidrug resistant. Carbapenems and nitrofurantoin for E. coli infections remain effective, which may guide empirical antibiotic therapy.
['Toner|Liam|L|', 'Papa|Nathan|N|', 'Aliyu|Sani H|SH|', 'Dev|Harveer|H|', 'Lawrentschuk|Nathan|N|', 'Al-Hayek|Samih|S|']
D000328:Adult D000368:Aged D000369:Aged, 80 and over D000900:Anti-Bacterial Agents D003428:Cross Infection D004926:Escherichia coli D004927:Escherichia coli Infections D005260:Female D006801:Humans D007709:Klebsiella D007710:Klebsiella Infections D008297:Male D008826:Microbial Sensitivity Tests D008875:Middle Aged D013997:Time Factors D014552:Urinary Tract Infections D001618:beta-Lactamases
Enterobacteriaceae Urinary tract infections Fluoroquinolones Nitrofurantoin Drug resistance, microbial