Virulence factors of uropathogenic Escherichia coli of urinary tract infections and asymptomatic bacteriuria in children.
OBJECTIVE
The clinical aspects of virulence genes of uropathogenic Escherichia coli (UPEC) are not fully understood. This study compared the presence of virulence genes in UPEC isolated from urinary tract infections (UTIs) and asymptomatic bacteriuria (ABU) in children.


METHODS
The study included children with UTI (n = 15) or ABU (n = 49) treated at Chung-Ang University Yongsan Hospital between 2010 and 2011. The strains were acquired from each urine sample collected, and 18 major virulence genes were detected by polymerase chain reaction. Antimicrobial susceptibility of all UPEC isolates was determined.


RESULTS
Sixty-four E. coli strains were isolated from the urine samples. The most commonly identified virulence gene in both groups was fimH (100.0% in the UTI group and 95.9% in the ABU group). The UTI isolates showed a higher prevalence of papEF and fyuA, and a lower prevalence of feoB than ABU isolates (p < 0.01 for all). The profile of virulence gene, fimH(+)kpsMTII(+)feoB(+) also showed a significant difference between the two groups (p < 0.01). Isolates from ABU were more resistant to most antimicrobials tested. The presence of papEF, feoB, and fyuA also correlated with the antimicrobial susceptibility of UPEC.


CONCLUSIONS
The virulence gene repertoire was different in the UPEC of UTI and ABU. The papEF, feoB, and fyuA genes showed meaningful differences between the two groups and may have an important role in the pathogenesis of overt UTI.
Department of Pediatrics, College of Medicine, Chung-Ang University, Seoul, South Korea.
Ki Wook
KW
Yun
Department of Pediatrics, College of Medicine, Chung-Ang University, Seoul, South Korea.
Hak Young
HY
Kim
Department of Microbiology, College of Medicine, Chung-Ang University, Seoul, South Korea.
Hee Kuk
HK
Park
Department of Microbiology, College of Medicine, Chung-Ang University, Seoul, South Korea.
Wonyong
W
Kim
Department of Pediatrics, College of Medicine, Chung-Ang University, Seoul, South Korea. Electronic address: pedwilly@gmail.com.
In Seok
IS
Lim
D001437:Bacteriuria / Q000382:microbiology*; D002648:Child; D002675:Child, Preschool; D004269:DNA, Bacterial / Q000235:genetics; D004927:Escherichia coli Infections / Q000382:microbiology*; D029968:Escherichia coli Proteins / Q000235:genetics*; D005260:Female; D006761:Hospitals; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008826:Microbial Sensitivity Tests; D016133:Polymerase Chain Reaction; D056910:Republic of Korea; D014552:Urinary Tract Infections / Q000382:microbiology*; D056689:Uropathogenic Escherichia coli / Q000235:genetics / Q000302:isolation & purification*; D037521:Virulence Factors / Q000235:genetics*
D004269:DNA, Bacterial; D029968:Escherichia coli Proteins; D037521:Virulence Factors
Asymptomatic bacteriuria; Urinary tract infection; Uropathogenic Escherichia coli; Virulence genes