OBJECTIVES: To characterize the beta-lactamase genes of the expanded-spectrum cephalosporin-resistant Escherichia coli isolates recovered in a Spanish hospital during the March 2002-March 2003 period. METHODS: Thirty-four of the 1700 E. coli isolates recovered from unrelated patients in a Spanish hospital showed expanded-spectrum cephalosporin resistance. The presence of genes encoding TEM, SHV, CTX-M, CMY-2-type or FOX beta-lactamases as well as the existence of mutations in the regulatory region of the chromosomal ampC gene were studied by PCR and sequencing in these 34 E. coli isolates. RESULTS: The following extended-spectrum beta-lactamases (ESBLs) or plasmidic class C beta-lactamase genes were detected (number of isolates): bla(CTX-M-14) (14), bla(CTX-M-9) (4), bla(CTX-M-32) (1), bla(TEM-52) (2), bla(SHV-12) (3) and bla(CMY-2) (2). The remaining eight isolates showed a mutation in the promoter/attenuator region of the ampC chromosomal gene at position -42, in combination with mutations at positions -18, -1 and +58. The bla(TEM-1) gene was also detected in 12 of the ESBL-producing isolates, in both CMY-2-producing isolates and in four of the eight isolates that showed a mutation at position -42 of the ampC promoter. Other mutations in the promoter/attenuator region were detected in association with ESBL or CMY-2 genes, such as the combination -18, -1 and +58, -28 and +58, or +22, +26, +27 and +32. No clonal relationship was found among the CTX-M-producing E. coli isolates by PFGE with XbaI enzyme. CONCLUSIONS: Approximately 1.5% of the E. coli isolates of our hospital harboured ESBL genes, those of the CTX-M-9 group being the most common ones.
OBJECTIVES: To characterize the beta-lactamase genes of the expanded-spectrum cephalosporin-resistant Escherichia coli isolates recovered in a Spanish hospital during the March 2002-March 2003 period. METHODS: Thirty-four of the 1700 E. coli isolates recovered from unrelated patients in a Spanish hospital showed expanded-spectrum cephalosporin resistance. The presence of genes encoding TEM, SHV, CTX-M, CMY-2-type or FOX beta-lactamases as well as the existence of mutations in the regulatory region of the chromosomal ampC gene were studied by PCR and sequencing in these 34 E. coli isolates. RESULTS: The following extended-spectrum beta-lactamases (ESBLs) or plasmidic class C beta-lactamase genes were detected (number of isolates): bla(CTX-M-14) (14), bla(CTX-M-9) (4), bla(CTX-M-32) (1), bla(TEM-52) (2), bla(SHV-12) (3) and bla(CMY-2) (2). The remaining eight isolates showed a mutation in the promoter/attenuator region of the ampC chromosomal gene at position -42, in combination with mutations at positions -18, -1 and +58. The bla(TEM-1) gene was also detected in 12 of the ESBL-producing isolates, in both CMY-2-producing isolates and in four of the eight isolates that showed a mutation at position -42 of the ampC promoter. Other mutations in the promoter/attenuator region were detected in association with ESBL or CMY-2 genes, such as the combination -18, -1 and +58, -28 and +58, or +22, +26, +27 and +32. No clonal relationship was found among the CTX-M-producing E. coli isolates by PFGE with XbaI enzyme. CONCLUSIONS: Approximately 1.5% of the E. coli isolates of our hospital harboured ESBL genes, those of the CTX-M-9 group being the most common ones.
Authors: S Peter-Getzlaff; S Polsfuss; M Poledica; M Hombach; J Giger; E C Böttger; R Zbinden; G V Bloemberg Journal: J Clin Microbiol Date: 2011-06-08 Impact factor: 5.948
Authors: Margaret A Davis; Thomas E Besser; Lisa H Orfe; Katherine N K Baker; Amelia S Lanier; Shira L Broschat; Daniel New; Douglas R Call Journal: Appl Environ Microbiol Date: 2011-03-18 Impact factor: 4.792
Authors: Miriam Barlow; Rebecca A Reik; Stephen D Jacobs; Mónica Medina; Matthew P Meyer; John E McGowan; Fred C Tenover Journal: Emerg Infect Dis Date: 2008-03 Impact factor: 6.883