title: Prevalence and characterization of extended spectrum β-lactamases in Klebsiella-Enterobacter-Serratia group bacteria, in Algeria.
abstract: OBJECTIVE
  The authors had for aim to assess the local epidemiology, antibiotic resistance, and molecular typing of expanded spectrum betalactamase producing Klebsiella, Enterobacter, and Serratia (ESBL KES).
  
  
  METHODS
  Two hundred and seven strains of the KES group were isolated in the microbiology laboratory of the Annaba Ibn Rochd hospital in 2009. The antibiotic resistance (diffusion method and MIC) was tested and ESBL detection was performed as recommended by the Clinical Laboratory Standard Institute (CLSI). The characterization of genes for resistance to β-lactams (CTX-M-1, TEM, and SHV) and AmpC cephalosporinase (DHA-1) was performed by polymerase chain reaction. The epidemiological relationship among identified strains was analyzed by Pulsed Field Gel Electrophoresis (PFGE). Genetic transfers were performed by conjugation using sodium azide resistant Escherichia coli K(12)J(5) as recipient strain.
  
  
  RESULTS
  The overall incidence of ESBL KES was 31.4% (65/207) distributed as follows: 17.4% of Klebsiella spp., 7.2% Enterobacter spp., and 6.8% Serratia marcescens. The β-lactamase CTX-M 1 types were predominant (88%), followed by TEM (36.5%), and SHV (31.1%). Twenty-three strains expressed at least two bla genes. DHA-1 type cephalosporinase was found in 4 E. cloacae associated with CTX-M-1. Several epidemic clones were determined. Conjugation experiments showed that bla(CTX-M), bla(TEM), and bla(SHV) were carried by conjugative plasmids of high molecular weight (≥125kb).
  
  
  CONCLUSIONS
  This study revealed a high frequency of ESBL KES with a predominance of CTX-M-1. This high rate of ESBLs could be due to a clonal spread and the emergence of new epidemic clones.
authors: Service de microbiologie, CHU Ibn Rochd, Annaba, Algeria. nedjaisabrina@yahooa.fr
authors: S
authors: S
authors: Nedjai
authors: A
authors: A
authors: Barguigua
authors: N
authors: N
authors: Djahmi
authors: L
authors: L
authors: Jamali
authors: K
authors: K
authors: Zerouali
authors: M
authors: M
authors: Dekhil
authors: M
authors: M
authors: Timinouni
mesh_terms: D000328:Adult; D000462:Algeria / Q000453:epidemiology; D001426:Bacterial Proteins / Q000032:analysis* / Q000235:genetics; D003428:Cross Infection / Q000453:epidemiology / Q000382:microbiology; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics; D004754:Enterobacter / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics; D004756:Enterobacteriaceae Infections / Q000453:epidemiology / Q000382:microbiology; D004926:Escherichia coli / Q000201:enzymology; D005260:Female; D006801:Humans; D007709:Klebsiella / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics; D007710:Klebsiella Infections / Q000453:epidemiology / Q000382:microbiology; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D010802:Phylogeny; D016133:Polymerase Chain Reaction / Q000379:methods; D011446:Prospective Studies; D011815:R Factors / Q000235:genetics; D016868:Serratia Infections / Q000453:epidemiology / Q000382:microbiology; D012706:Serratia marcescens / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics; D013379:Substrate Specificity; D014169:Transformation, Bacterial; D055815:Young Adult; D018440:beta-Lactam Resistance / Q000235:genetics; D001618:beta-Lactamases / Q000032:analysis* / Q000235:genetics
chemical_list: D001426:Bacterial Proteins; D001618:beta-Lactamases