Expression of virulence factors among Escherichia coli isolated from the periurethra and urine of children with neurogenic bladder on intermittent catheterization.
BACKGROUND
Patients with neurogenic bladder caused by spinal cord injury or myelomeningocele empty their bladder several times a day by intermittent catheterization. Bacteriuria without symptoms of infection is frequently present in these patients. Occasionally a clone of Escherichia coli that has been carried for weeks without symptoms causes a symptomatic urinary tract infection. Virulence factors are commonly expressed among E. coli causing infection in patients with normal urinary tracts. However, it is unknown whether expression of virulence factors by an E. coli clone colonizing the neurogenic bladder increases the risk of subsequent infection. In this study we examined the prevalence of virulence factor expression among E. coli isolated from the periurethra and urine of patients with neurogenic bladder.


METHODS
The prevalence of virulence factors was examined among E. coli isolated from the periurethra and urine in patients with neurogenic bladder who received intermittent catheterization and were followed for 6 months. Representative isolates from the 37 clonal types of E. coli detected in the periurethra and urine of children with neurogenic bladder were assessed for O antigen, hemolysin, aerobactin, serum resistance and type I and P-adhesin.


RESULTS
All clones were serum-resistant and expressed type I adhesin, none expressed aerobactin and two expressed hemolysin. The presence of P-adhesin was not unique to clones associated with symptomatic infection. The presence of P-adhesin carried for weeks in a clone did not predict subsequent infection in the neurogenic bladder.


CONCLUSIONS
Bacterial virulence factors did not predict infection of the neurogenic bladder.
Schlager
T A
TA
Department of Emergency Medicine, University of Virginia, Charlottsville, Department of Emergency Medicine, 22906-0014, USA. tas8n@virginia.edu
Whittam
T S
TS
Hendley
J O
JO
Wilson
R A
RA
Bhang
J
J
Grady
R
R
Stapleton
A
A
D000293:Adolescent; D000900:Anti-Bacterial Agents / Q000008:administration & dosage; D002648:Child; D002675:Child, Preschool; D015169:Colony Count, Microbial; D004926:Escherichia coli / Q000187:drug effects / Q000472:pathogenicity*; D004927:Escherichia coli Infections / Q000175:diagnosis / Q000453:epidemiology*; D005260:Female; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D015995:Prevalence; D012307:Risk Factors; D012680:Sensitivity and Specificity; D014521:Urethra / Q000382:microbiology*; D001750:Urinary Bladder, Neurogenic / Q000382:microbiology* / Q000628:therapy; D014546:Urinary Catheterization / Q000009:adverse effects / Q000379:methods; D014556:Urine / Q000382:microbiology*; D014774:Virulence
D000900:Anti-Bacterial Agents