Community infections caused by extended-spectrum beta-lactamase-producing Escherichia coli.
BACKGROUND
Extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli is an increasingly important group of community pathogens worldwide. These organisms are frequently resistant to many of the antimicrobial agents usually recommended for the treatment of infections caused by E coli, such as penicillins, cephalosporins, fluoroquinolones, and trimethoprim-sulfamethoxazole. Data concerning risk factors, clinical features, and therapeutic options for such infections are scarce.


METHODS
A case-control study was performed to investigate the risk factors for all types of community-acquired infections caused by ESBL-producing E coli in 11 Spanish hospitals from February 2002 to May 2003. Controls were randomly chosen from among outpatients with a clinical sample not yielding ESBL-producing E coli. The clinical features of these infections were investigated in the case patients. The efficacy of fosfomycin tromethamine and amoxicillin-clavulanate potassium was observationally studied in patients with cystitis.


RESULTS
A total of 122 cases were included. Risk factors selected by multivariate analysis included the following: age older than 60 years; female sex; diabetes mellitus; recurrent urinary tract infections (UTIs); previous invasive procedures of the urinary tract; follow-up in outpatient clinic; and previous receipt of aminopenicillins, cephalosporins, and fluoroquinolones. Urinary tract infections accounted for 93% of the cases; 6% of the patients were bacteremic and 10% needed hospitalization. The cure rate of patients with cystitis was 93% with fosfomycin therapy (all isolates were susceptible); among patients treated with amoxicillin-clavulanate, cure rates were 93% for those with susceptible isolates (minimum inhibitory concentration < or =8 microg/mL) and 56% for those with intermediate or resistant isolates (minimum inhibitory concentration > or =16 microg/mL) (P = .02).


CONCLUSIONS
In predisposed patients, ESBL-producing E coli is a notable cause of community-acquired infection, and particularly UTI. Fosfomycin and amoxicillin-clavulanate appear to be effective for cystitis caused by susceptible isolates.
Rodríguez-Baño
Jesús
J
Sección de Enfermedades Infecciosas, Hospital Universitario Virgen Macarena, Avda Dr Fedriani, 3, 41009 Seville, Spain. jrb@nacom.es
Alcalá
Juan C
JC
Cisneros
Jose M
JM
Grill
Fabio
F
Oliver
Antonio
A
Horcajada
Juan P
JP
Tórtola
Teresa
T
Mirelis
Beatriz
B
Navarro
Gemma
G
Cuenca
María
M
Esteve
María
M
Peña
Carmen
C
Llanos
Ana C
AC
Cantón
Rafael
R
Pascual
Alvaro
A
D000367:Age Factors; D019980:Amoxicillin-Potassium Clavulanate Combination / Q000494:pharmacology / Q000627:therapeutic use; D000900:Anti-Bacterial Agents / Q000494:pharmacology / Q000627:therapeutic use; D016022:Case-Control Studies; D017714:Community-Acquired Infections / Q000188:drug therapy / Q000382:microbiology*; D003556:Cystitis / Q000382:microbiology; D048909:Diabetes Complications; D024881:Drug Resistance, Bacterial; D004926:Escherichia coli / Q000187:drug effects / Q000201:enzymology* / Q000302:isolation & purification*; D005260:Female; D005578:Fosfomycin / Q000494:pharmacology / Q000627:therapeutic use; D006801:Humans; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D013030:Spain; D014552:Urinary Tract Infections / Q000150:complications / Q000188:drug therapy / Q000382:microbiology*; D001618:beta-Lactamases / Q000096:biosynthesis*
D000900:Anti-Bacterial Agents; D005578:Fosfomycin; D019980:Amoxicillin-Potassium Clavulanate Combination; D001618:beta-Lactamases