Incidence of antibiotic-resistant Escherichia coli bacteriuria according to age and location of onset: a population-based study from Olmsted County, Minnesota.
OBJECTIVE
To better understand the epidemiology of drug-resistant Escherichia coli across health care and community settings.


METHODS
We conducted a population-based cohort study of the incidence of antibiotic-resistant E coli bacteriuria among different patient groups. All urine cultures with monomicrobial growth of E coli obtained from Olmsted County, Minnesota, residents from January 1, 2005, through December 31, 2009, were identified. The initial isolate per patient per year was included. Analyses were stratified by patient age and location of infection onset (ie, nosocomial, health care associated, and community associated).


RESULTS
We evaluated 5619 E coli isolates and the associated patients. During the study period, the incidence of drug-resistant bacteriuria did not change among children but increased significantly among adults of all ages, most markedly among elderly patients older than 80 years. In elderly patients, the incidence of bacteriuria with isolates resistant to fluoroquinolones increased from 464 to 1116 per 100,000 person-years (P<.001), and the incidence of bacteriuria with isolates resistant to fluoroquinolones plus trimethoprim-sulfamethoxazole increased from 274 to 512 per 100,000 person-years (P<.05). When analyzed by location of infection onset, incidence of bacteriuria with isolates resistant to trimethoprim-sulfamethoxazole, fluoroquinolones, trimethoprim-sulfamethoxazole plus fluoroquinolones, extended-spectrum cephalosporins, and more than 3 drug classes increased significantly among community-associated but not among nosocomial or health care-associated cases.


CONCLUSIONS
In this population-based study, the incidence of antibiotic-resistant E coli bacteriuria nearly doubled during the 5-year study period among elderly patients and those with community-associated isolates. These patient groups should be targets of interventions to slow the emergence and spread of antibiotic-resistant E coli.
Division of Infectious Diseases, Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, USA.
Sanjeev K
SK
Swami
Juliette T
JT
Liesinger
Nilay
N
Shah
Larry M
LM
Baddour
Ritu
R
Banerjee
D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D001437:Bacteriuria / Q000188:drug therapy* / Q000453:epidemiology / Q000382:microbiology; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D017714:Community-Acquired Infections / Q000188:drug therapy / Q000453:epidemiology / Q000382:microbiology; D003428:Cross Infection / Q000188:drug therapy / Q000453:epidemiology / Q000382:microbiology; D024901:Drug Resistance, Multiple, Bacterial; D004927:Escherichia coli Infections / Q000188:drug therapy* / Q000453:epidemiology; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D008910:Minnesota / Q000453:epidemiology; D011159:Population Surveillance; D012189:Retrospective Studies; D055815:Young Adult
D000900:Anti-Bacterial Agents