Clinical and Molecular Analysis of Extended-Spectrum β-Lactamase-Producing Enterobacteria in the Community Setting

Abstract

During a previous survey, five extended-spectrum ␤-lactamase (ESBL)-producing enterobacteria (ESBLE) (two Enterobacter aerogenes isolates expressing TEM-24b, two Escherichia coli isolates expressing TEM-21 or TEM-24b, and one Klebsiella pneumoniae isolate expressing SHV-4/TEM-15) responsible for urinary tract infections (UTIs) were found among 1,584 strains collected from community patients. The aim of the present study was to elucidate the route of emergence of these typically nosocomial organisms in the community. Thus, the files of the five patients were analyzed over at least a decade, and potentially related ESBLE from hospitals or clinics were examined. Their enzymes were characterized at a molecular level, and the strains were typed by amplified-primed PCR, enterobacterial repetitive intergenic consensus PCR, and restriction plasmid profile. All patients (C1 to C5) had risk factors for ESBLE acquisition, including past history of hospitalization (2.5 to 23 months before). Four (C1 and C3 to C5) had previously received antibiotics (concomitantly to 35 months earlier), two (C1 and C3) had indwelling urinary catheters and recurrent UTIs, and three (C2, C3, and C5) formerly experienced ESBLE-induced UTIs (2 1 ⁄2 to 11 1 ⁄2 months before). The same ESBLE and/or an identical or similar ESBL-encoding plasmid was identified in the hospital ward (C1 to C4) or in a clinic (C5) where the patients had previously resided. Patients C1 and C4, infected with different ESBLE carrying a closely related plasmid, were hospitalized in the same unit. Persistence of ESBLE over at least a 5-year period was demonstrated for patient C3. Thus, community-acquired UTIs in these patients likely resulted from nosocomially acquired ESBLE or an ESBL-encoding plasmid followed by a prolonged digestive carriage.Extended-spectrum ␤-lactamase (ESBL)-producing enterobacteria (ESBLE) have emerged at the end of the 1980s within hospitals, causing outbreaks and/or hyperendemic situations in many centers. Several recent data have suggested that ESBLE are currently emerging within the community

Large Dissemination of VIM-2-Metallo-β-Lactamase-Producing Pseudomonas aeruginosa Strains Causing Health Care-Associated Community-Onset Infections

“…This fact further supports the horizontal migration of P. aeruginosa from the hospital environment to the community setting. Consistent with our observations, previous studies have also demonstrated that community-onset infections due to ESBL-producing gram-negative bacteria often result from nosocomial acquisition of the strains or their genetic elements (1). Moreover, genitourinary pathology, a finding common in our patients, has been recognized as an independent risk factor for community-onset infections caused by ESBL-producing organisms (2).…”

The continuing challenge of ESBLs

“…Nursing homes, in turn, may serve as reservoirs from which colonized and infected patients transfer to the community or back to the hospitals [8,32]. Prior to the rise of CTX-M, such a model seemed to have corresponded with the available data [33]. Even after the noted spread of bacteria producing CTX-M into the community, recent hospitalization, along with age and exposure to cephalosporins and/or quinolones, have consistently been identified as risk factors for infection with these organisms [8,34,35].…”

Sensitivity of urinary pathogens to antimicrobial therapy in patients from primary health care

“…Porast rezistencije uropatogena bio je mnogo veći problem bolničkih sredina. Međutim, studijama sprovedenim u poslednjih deset godina, pokazan je porast rezistentnih sojeva i u opštoj populaciji (20)(21)(22)(23)(24)(25). iz ovog razloga, treba biti obazriv prilikom empirijskog propisivanja terapije, naročito ako se radi o starijim osobama, osobama s hroničnim oboljenjima, ili osobama s malformacijama urinarnog trakta.…”