Carbapenem-hydrolyzing oxacillinase, OXA-48, persists in Klebsiella pneumoniae in Istanbul, Turkey

Aktas Z. , Kayacan C. B. , Schneider I., Can B. , Midilli K. , Bauernfeind A.

CHEMOTHERAPY, cilt.54, ss.101-106, 2008 (SCI İndekslerine Giren Dergi) identifier identifier identifier

  • Cilt numarası: 54 Konu: 2
  • Basım Tarihi: 2008
  • Doi Numarası: 10.1159/000118661
  • Sayfa Sayıları: ss.101-106


Background: Two OXA-48-producing Klebsiella pneumoniae isolates (KP-4936 and KP-154488) were analyzed. Method: Minimum inhibitory concentrations were determined using agar dilution and E-test, beta-lactamase production by phenotypic tests (E-test MBL and ESBL, isoelectric focusing, and bioassay) and molecular methods (PCR, RAPD-PCR, sequencing, plasmid analysis, and conjugation). Results: Isolates were resistant to all beta-lactams, including carbapenems. PCR and sequencing identified bla(OXA-48) in both isolates and the transconjugant. KP-4936 harbored bla(TEM-1) (pI 5.4) and bla(CTX-M-15) genes (pI 8.6), while KP-154488 was positive for bla(TEM-1) (pI 5.4), bla(CTX-M-15) (pI 8.9), and bla(SHV2a) (pI 7.6), in addition. The enzyme with a pI of 7.2 hydrolyzed imipenem according to a bioassay result. Plasmids (70 and 140 kb) from KP-4936 were transferred by conjugation. RAPD-PCR found no clonal relationship between the two strains. Conclusion: Carbapenem resistance may spread among Enterobacteriaceae via the transferable enzyme OXA-48. Copyright (c) 2008 S. Karger AG, Basel.