Extended-spectrum β-lactamase-producing pathogens in a children's hospital: A 5-year experience

Division of Pediatric Infectious Diseases, Department of Pediatrics, University of Utah, PO Box 581289, Salt Lake City, UT 84158, USA.
American journal of infection control (Impact Factor: 2.21). 02/2009; 37(6):435-41. DOI: 10.1016/j.ajic.2008.09.019
Source: PubMed


Pediatric infection with bacteria producing extended-spectrum beta-lactamases (ESBLs) has not been well described. We sought to determine the proportion of isolates producing ESBLs and the incidence of infection or colonization with these organisms in our tertiary care pediatric facility over 5 years. In addition, we sought to evaluate the characteristics of children affected.
We identified all Escherichia coli or Klebsiella spp cultured from children younger than 18 years of age at our facility between January 2003 and December 2007. Medical records were reviewed for affected children.
Of 2697 E coli, K pneumoniae, and K oxytoca cultured, 26 ESBL producers were isolated from 16 children. Rates of ESBL production among cultured isolates significantly increased, from 0.53% in the first half of the study period to 1.4% in the second. Incidence of a primary ESBL infection also increased significantly, from 0.14/10,000 patient encounters to 0.31/10,000. The majority of children infected or colonized with ESBL-producing organisms were those with chronic medical conditions, frequent hospitalizations, or a history of recurrent infection. However, 4 affected children were less than 5 months old and evaluated in an outpatient setting.
Rates and incidence of ESBL infection increased over the study period. Whereas most patients belonged to traditional risk groups for antibiotic-resistant infection, infants in the ambulatory setting were also affected, an at-risk population not previously described.

Download full-text


Available from: Judy A Daly,
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Background and Objective: To evaluate extended spectrum betalactamase (ESBL) positive strains of Klebsiella pneumonia and Escherichia coli in positive bacterial cultures. Materials and Methods: In this analytical cross-sectional study, between March 2006 and March 2007, 170 bacterial isolates including 133 cases of E. coli and 37cases of K. pneumonia were examined. All cases underwent double disk diffusion for ESBL. Demographic data were assessed and all data analyzed accordingly. Results: Patients' mean age was 55 ±26.63 yr. Ninety six cases (56.5%) were female and 74 cases (43.5%) were male. Clinical presentation of infection were 118 cases UTI (96.4%), 15 cases septicemia (8.8%), 16cases wound infection (9.4%), 7 cases pneumonia (4.1%), 1 case meningitis (0.6%) and 13 cases other presentations (7.6%). Frequency of ESBL positive in E. coli isolates was 38 cases (28.6%) and in K. pneumonia isolates was 10 cases (27%). There was no significant correlation between ESBL positivity and age, gender, ward or clinical presentation of infection. Conclusion: Incidence of ESBL positive isolates of E. coli and K. pneumonia was high. These results should be considered in administration of broad-spectrum antibiotics by clinicians.
  • [Show abstract] [Hide abstract]
    ABSTRACT: Of forty-seven extended-spectrum cephalosporin-resistant Escherichia coli isolates, collected from children at the Children's Hospital in 2006 (Tunis, Tunisia), we analyzed 32 isolates that were genotypically different by enterobacterial repetitive intergenic consensus -polymerase chain reaction. For all isolates, the double-disk diffusion test revealed synergy between clavulanate and cefotaxime and/or ceftazidime, suggesting the production of extended-spectrum beta-lactamases. Polymerase chain reaction experiments, performed on plasmid DNA, and sequencing revealed the presence of bla(TEM-1B) (26 isolates, 81%), bla(TEM-34(IRT-6)) (3 isolates, 9%), bla(SHV-12) (2 isolates, 6%), and bla(CTX-M-15) (31 isolates, 97%). Further, the insertion sequence ISEcp1 was found upstream from the bla(CTX-M-15) gene in 11 isolates. The bla genes were found alone or in various combinations in a single isolate. bla(TEM-1B) and bla(CTX-M-15) genes were detected in 26 out of the 32 isolates. Three isolates harbored both bla(TEM-34(IRT-6)) and bla(CTX-M-15). bla(SHV-12) was identified either alone or with bla(CTX-M-15) in a single isolate. Our investigation showed the dominance of CTX-M-type extended-spectrum beta-lactamases, with CTX-M-15 particularly common, and to our best knowledge, this is the first report of the coexistence of CTX-M-15 and IRT-6 in E. coli isolates from children in Tunisia.
    Microbial drug resistance (Larchmont, N.Y.) 02/2011; 17(2):135-40. DOI:10.1089/mdr.2010.0098 · 2.49 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: To analyse the prevalence of resistance to β-lactams and plasmid-mediated quinolone resistance in Enterobacteriaceae in the paediatric hospital of Uruguay. A total of 368 enterobacterial isolates collected between 1 May and 30 November 2009 were studied for the presence of extended-spectrum β-lactamases (ESBLs), qnr alleles and aac(6')Ib by phenotypic and molecular methods. The genomic context and transferability of β-lactamase and qnr genes were examined by PCR and conjugation, respectively. The proportion of inpatients having an infection caused by ESBL-producing enterobacteria was 0.23% (16/7073) in paediatrics wards, 0.64‰ (3/4696) in the neonatology department and 0.03‰ (1/32 557) in the emergency department. ESBL-carrying enterobacteria constituted a total of 21.6% (16/74), 13% (3/23) and 0.37% (1/271) when samples were obtained from paediatrics wards, the neonatology department and the emergency department, respectively. Overall, CTX-M-2 (n = 7), CTX-M-9 (n = 3), CTX-M-8 (n = 2), CTX-M-15 (n = 1), SHV-5 (n = 5) and SHV-2 (n = 2) β-lactamases were detected. Thirteen out of 20 ESBL-producing isolates also carried the aac(6')Ib gene, and the cr variant was detected in one of them. qnr alleles were detected in four isolates comprising two qnrA1 genes, a qnrB8-like variant and a new qnrB gene showing 26 amino acid differences from QnrB1. The proportion of ESBL-producing enterobacteria in Uruguay's paediatric hospital during the study period was 2.3 per 1000 hospitalized patients. The number of different microorganisms detected, as well as the various EBSLs, suggests the occurrence of sporadic episodes instead of nosocomial outbreaks. Nevertheless, the presence of new resistance genes reinforces the necessity for permanent surveillance programmes.
    Journal of Antimicrobial Chemotherapy 06/2011; 66(8):1725-9. DOI:10.1093/jac/dkr222 · 5.31 Impact Factor
Show more