Clinical and molecular epidemiology of community-onset, extendedspectrum β-lactamase-producing Escherichia coli infections in Thailand:: A case-case-control study

Background: Extended-spectrum P-lactamase (ESBL)-producing organisms, first identified in Germany in 1983, are now widely recognized as clinically relevant causes of infections in community Methods: Our objective was to evaluate the clinical and molecular epidemiology of community-onset, extended- spectrum P-lactamase (CO-ESBL)-producing Escherichia coli infections. We used a case-case-control study undertaken in a 450-bed, tertiary care hospital. Patients included case group (CG) 1, which had confirmed CO-ESBL-producing E coli infections (n = 46). Case group (CG) II (n = 46) included patients with CO-non-ESBL-producing E coli infections. Controls (n = 138) were patients without infections. Results: By multivariate analysis, diabetes (95 % confidence interval [CI]: 1.9-13.2, P <.001), prior ESBL E coli colonization (<90 days) (95 % CI: 1.2-67.8, P <.001), recent receipt of antibiotics (<90 days) (95 % CI: 4.2-44.2, P =.004), and previous exposure to third-generation cephalosporins (95 % Cl: 2.2-16.4, P =.001) and fluoroquinolones (95 % CI: 1.4-18.3; P = -003) were associated risks among CG I. Diabetes (95 % CI: 1.6-15.4, P =.005), stroke (95 % CI: 1.5-17. 1, P =.001), and diarrhea (95 % CI: 3.8-65.8, P =.001) were risks among CG II. Patients with CO-ESBL in CG I versus controls were more likely to die (30 % vs 0%, respectively; P <.001), had prolonged hospital length of stay (8 vs 5 days, respectively; P <.001), and had higher hospitalization costs (median, US $528 vs $108, respectively; P <.001). The plasmid carrying the CTX-M-15 gene was identified in 13 of 25 (52 %) available CO-ESBL-producing E coli isolates. Conclusion: CO-ESBL-producing E coli is an emerging multidrug-resistant microorganism in Thailand. Patients with prior ESBL colonization and recent antibiotic exposures, especially to third-generation cephalosporins and fluoroquinolones, were at risk for CO-ESBL-producing E coli infection.