Epidemiology and Risk Factors of Community Onset Infections Caused by Extended-Spectrum β-Lactamase-Producing Escherichia coli Strains

Abstract

Limited clinical information is available regarding community onset infections caused by extended-spectrum ␤-lactamase (ESBL)-producing Escherichia coli. A case-control study was performed to evaluate the epidemiology and risk factors of these types of infections. A case patient was defined as a person whose clinical sample yielded ESBL-producing E. coli. For each case patient, one control was randomly chosen from a group of outpatients from whom non-ESBL-producing E. coli had been isolated and for whom a clinical sample had been sent to the same laboratory for culturing during the following week. Of 108 cases of ESBL-producing E. coli, 56 (51.9%) were classified as health care associated (HCA). Univariate analysis showed male gender, HCA infection, severe underlying illness, and a prior receipt of antibiotics to be associated with ESBL-producing E. coli. In the multivariate analysis, HCA infection (odds ratio [OR], 3.18; 95% confidence interval [CI], 1.67 to 6.06; P < 0.001) and previous use of antibiotics (OR, 4.88; 95% CI, 2.08 to 11.48; P < 0.001) were found to be significantly associated with the ESBL group. In a multivariate analysis that included each antibiotic, previous use of fluoroquinolone (OR, 7.32; 95% CI, 1.58 to 34.01; P ‫؍‬ 0.011) was significantly associated with ESBL-producing E. coli. Of 101 isolates in which ESBLs and their molecular relationships were studied, all isolates produced ESBLs from the CTX-M family (CTX-M-14, 40 isolates; CTX-M-15, 39 isolates; and other members of the CTX-M family, 22 isolates). In conclusion, this study confirms that ESBL-producing E. coli strains are a notable cause of community onset infections in predisposed patients. HCA infection and previous use of fluoroquinolone were significant factors associated with ESBL-producing E. coli in community onset infections. During the past 2 decades, antimicrobial-resistant strains that produce extended-spectrum ␤-lactamases (ESBLs) have emerged among Enterobacteriaceae, predominantly among Escherichia coli and Klebsiella pneumoniae (5,20,21). Subsequently, ESBL-producing E. coli has gained worldwide recognition as a significant group of community-acquired pathogens (3, 22). Although most patients with community onset infections caused by these organisms have urinary tract infections (UTIs), some patients present with intra-abdominal infections and concomitant bacteremia (12, 23). Nevertheless, there is still limited information about the clinical epidemiology of community onset ESBLproducing E. coli infections. Previous studies describing the clinical and microbiological epidemiology of ESBL-producing E. coli infections have focused mainly on UTIs (2, 4, 16, 22).Because ESBL-producing organisms are frequently resistant to multiple antimicrobial agents, therapeutic options for these infections are limited (18). At present, carbapenems are recommended for the treatment of serious infections caused by ESBL-producing organisms. Given the increasing incidence and pathogenic significance of ESBL-producing E. coli in community ...

Prevalence and risk factors of extended-spectrum β-lactamases producing Enterobacteriaceae in a general hospital in Saudi Arabia

“…Community acquired ESBL associated infections are mostly urinary tract infections (UTIs), however some patients suffer from intra-abdominal infections and bacteremia. 1 In Our study (33%) of ESBL associated infections were acquired within two days of admission. Similarly, Ben Ami et al showed that the prevalence of community acquired ESBL associated infections was 34.6%.19 On the other hand, in a study conducted in the eastern region of Saudi Arabia, only 37.9% of the bacteremia due to ESBL producing isolates were hospital acquired.…”

“…4 Presently, carbapenems became the first line antimicrobials for the treatment of such infections. 1 The spread of ESBLs has certain consequences such as hindering effective treatment, poor outcomes, prolonged hospitalization and increase treatment costs. 5 Risk factors for ESBLs associated infections include patients' prior comorbidities (such as diabetes mellitus, renal failure, immunosuppression, neoplastic diseases, etc.…”

“…1 Β-lactamases are enzymes that hydrolysis β-lactam ring thus destroying the activity of β lactam antibiotics. ESBLs were discovered in 1983 and they can hydrolyze oxyimino-cephalosporins, and monobactams, but not cephamycins or carbapenems.…”

Population-Based Epidemiology and Microbiology of Community-Onset Bloodstream Infections

“…However, since the turn of the millennium, these have emerged as major communityonset pathogens worldwide (207,212). Series of community-onset BSIs due to a range of ESBL-producing Enterobacteriaceae have been reported from around the globe (13,81,(213)(214)(215)(216). Molecular epidemiology studies have identified a globally distributed clone, ST131, and defined the importance of international travel in the acquisition and spread of these infections (217)(218)(219)(220)(221)(222).…”

In Vitro Activities of 21 Antimicrobial Agents Alone and in Combination with Aminoglycosides or Fluoroquinolones against Extended-Spectrum-β-Lactamase-Producing Escherichia coli Isolates Causing Bacteremia

“…ESBL activity was confirmed via a double-disk synergy test (ceftazidime, cefotaxime, and aztreonam MICs of Ն2 mg/liter) using BD BBL Sensi-Discs (BD Diagnostics, Sparks, MD). ESBL-related genes, including bla TEM , bla SHV , and bla CTX-M , were amplified by PCR as described previously (7,8). Statistical analysis was performed using SPSS for Windows (version 11.5 software; SPSS, Inc., Chicago, IL).…”