Escherichia coli isolates causing asymptomatic bacteriuria in catheterized and noncatheterized individuals possess similar virulence properties

TY - JOUR

T1 - Escherichia coli isolates causing asymptomatic bacteriuria in catheterized and noncatheterized individuals possess similar virulence properties

AU - Watts, Rebecca E

AU - Hancock, Viktoria

AU - Ong, Cheryl-Lynn Y

AU - Vejborg, Rebecca Munk

AU - Mabbett, Amanda N

AU - Totsika, Makrina

AU - Looke, David F

AU - Nimmo, Graeme R

AU - Klemm, Per

AU - Schembri, Mark A

PY - 2010/7/1

Y1 - 2010/7/1

N2 - Urinary tract infections (UTIs) are among the most common infectious diseases of humans, with Escherichia coli being responsible for >80% of all cases. Asymptomatic bacteriuria (ABU) occurs when bacteria colonize the urinary tract without causing clinical symptoms and can affect both catheterized patients (catheter-associated ABU [CA-ABU]) and noncatheterized patients. Here, we compared the virulence properties of a collection of ABU and CA-ABU nosocomial E. coli isolates in terms of antibiotic resistance, phylogenetic grouping, specific UTI-associated virulence genes, hemagglutination characteristics, and biofilm formation. CA-ABU isolates were similar to ABU isolates with regard to the majority of these characteristics; exceptions were that CA-ABU isolates had a higher prevalence of the polysaccharide capsule marker genes kpsMT II and kpsMT K1, while more ABU strains were capable of mannose-resistant hemagglutination. To examine biofilm growth in detail, we performed a global gene expression analysis with two CA-ABU strains that formed a strong biofilm and that possessed a limited adhesin repertoire. The gene expression profile of the CA-ABU strains during biofilm growth showed considerable overlap with that previously described for the prototype ABU E. coli strain, 83972. This is the first global gene expression analysis of E. coli CA-ABU strains. Overall, our data suggest that nosocomial ABU and CA-ABU E. coli isolates possess similar virulence profiles.

AB - Urinary tract infections (UTIs) are among the most common infectious diseases of humans, with Escherichia coli being responsible for >80% of all cases. Asymptomatic bacteriuria (ABU) occurs when bacteria colonize the urinary tract without causing clinical symptoms and can affect both catheterized patients (catheter-associated ABU [CA-ABU]) and noncatheterized patients. Here, we compared the virulence properties of a collection of ABU and CA-ABU nosocomial E. coli isolates in terms of antibiotic resistance, phylogenetic grouping, specific UTI-associated virulence genes, hemagglutination characteristics, and biofilm formation. CA-ABU isolates were similar to ABU isolates with regard to the majority of these characteristics; exceptions were that CA-ABU isolates had a higher prevalence of the polysaccharide capsule marker genes kpsMT II and kpsMT K1, while more ABU strains were capable of mannose-resistant hemagglutination. To examine biofilm growth in detail, we performed a global gene expression analysis with two CA-ABU strains that formed a strong biofilm and that possessed a limited adhesin repertoire. The gene expression profile of the CA-ABU strains during biofilm growth showed considerable overlap with that previously described for the prototype ABU E. coli strain, 83972. This is the first global gene expression analysis of E. coli CA-ABU strains. Overall, our data suggest that nosocomial ABU and CA-ABU E. coli isolates possess similar virulence profiles.

KW - Adolescent

KW - Adult

KW - Aged

KW - Aged, 80 and over

KW - Bacteriuria

KW - Biofilms

KW - Catheters, Indwelling

KW - Drug Resistance, Bacterial

KW - Escherichia coli

KW - Female

KW - Gene Expression Profiling

KW - Genes, Bacterial

KW - Humans

KW - Iron

KW - Male

KW - Microbial Sensitivity Tests

KW - Middle Aged

KW - Oligonucleotide Array Sequence Analysis

KW - Phylogeny

KW - Urinary Catheterization

KW - Virulence Factors

KW - beta-Lactam Resistance

U2 - 10.1128/JCM.01611-09

DO - 10.1128/JCM.01611-09

M3 - Journal article

C2 - 20444967

SN - 0095-1137

VL - 48

SP - 2449

EP - 2458

JO - Journal of Clinical Microbiology

JF - Journal of Clinical Microbiology

IS - 7

ER -