Emerging Escherichia coli O25b/ST131 clone predicts treatment failure in urinary tract infections.
BACKGROUND
We described the clinical predictive role of emerging Escherichia coli O25b/sequence type 131 (ST131) in treatment failure of urinary tract infection.


METHODS
In this prospective observational cohort study, the outpatients with acute cystitis with isolation of E. coli in their urine cultures were assessed. All the patients were followed up for clinical cure after 10 days of treatment. Detection of the E. coli O25:H4/ST131 clone was performed by multiplex polymerase chain reaction (PCR) for phylogroup typing and using PCR with primers for O25b rfb and allele 3 of the pabB gene.


RESULTS
In a cohort of patients with diagnosis of acute urinary cystitis, 294 patients whose urine cultures were positive with a growth of >10(4) colony-forming units/mL of E. coli were included in the study. In empiric therapy, ciprofloxacin was the first choice of drug (27%), followed by phosphomycin (23%), trimethoprim-sulfamethoxazole (TMP-SMX) (9%), and cefuroxime (7%). The resistance rate was 39% against ciprofloxacin, 44% against TMP-SMX, and 25% against cefuroxime. Thirty-five of 294 (12%) isolates were typed under the O25/ST131 clone. The clinical cure rate was 85% after the treatment. In multivariate analysis, detection of the O25/ST131 clone (odds ratio [OR], 4; 95% confidence interval [CI], 1.51-10.93; P = .005) and diabetes mellitus (OR, 2.1; 95% CI, .99-4.79; P = .05) were found to be significant risk factors for the treatment failure. In another multivariate analysis performed among quinolone-resistant isolates, treatment failure was 3 times more common among the patients who were infected with ST131 E. coli (OR, 3; 95% CI, 1.27-7.4; P = .012).


CONCLUSIONS
In urinary tract infections, the E. coli ST131 clone seems to be a consistent predictor of treatment failure.
Department of Medical Microbiology, Koç University, School of Medicine, Istanbul.
Fusun
F
Can
Department of Infectious Diseases, Baskent University, School of Medicine, Ankara.
Ozlem Kurt
OK
Azap
Department of Medical Microbiology, Koç University, School of Medicine, Istanbul.
Ceren
C
Seref
Department of Medical Microbiology, Koç University, School of Medicine, Istanbul.
Pelin
P
Ispir
Department of Infectious Diseases, Baskent University, School of Medicine, Ankara.
Hande
H
Arslan
Department of Infectious Diseases, Koç University, School of Medicine, Istanbul, Turkey.
Onder
O
Ergonul
D000368:Aged; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D015373:Bacterial Typing Techniques; D002444:Cefuroxime / Q000627:therapeutic use; D002939:Ciprofloxacin / Q000627:therapeutic use; D015331:Cohort Studies; D003556:Cystitis / Q000188:drug therapy / Q000382:microbiology*; D024901:Drug Resistance, Multiple, Bacterial / Q000187:drug effects; D004926:Escherichia coli / Q000145:classification / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification; D004927:Escherichia coli Infections / Q000188:drug therapy* / Q000382:microbiology*; D005260:Female; D005544:Forecasting; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D060885:Multiplex Polymerase Chain Reaction; D015999:Multivariate Analysis; D010802:Phylogeny; D011446:Prospective Studies; D017211:Treatment Failure; D015662:Trimethoprim, Sulfamethoxazole Drug Combination / Q000627:therapeutic use; D014421:Turkey; D014552:Urinary Tract Infections / Q000188:drug therapy / Q000382:microbiology*
D000900:Anti-Bacterial Agents; D002939:Ciprofloxacin; D015662:Trimethoprim, Sulfamethoxazole Drug Combination; D002444:Cefuroxime
E. coli; ST131; treatment failure; urinary