TABLE 3.

Laboratory diagnosis of control strains producing known ESBLs

StrainEnzymeResult by:a:
ScreeningbDisk confirmationcPCR primer pairsd
CPDCAZCTXCAZ/CLACTX/CLACTX-M-I groupCTX-M-II groupCTX-M-III groupCTX-M-IV group
CF2CTX-M-1+++++
Rio-4CTX-M-2++++
VER-1CTX-M-3+++++
Cfr2525/96CTX-M-3+++++
Eco3553/98CTX-M-15++++++
34CTX-M-5+++++
Rio-3CTX-M-8++++
785DCTX-M-9++++
EC97/38582CTX-M-10++++
EC984167CTX-M-14++++
CF1CTX-M-14++++
Rio-6CTX-M-16++++++
BM4493CTX-M-17++++++
ILT-2CTX-M-18+++++
ILT-3CTX-M-19++++++
CT1Toho-1++++
S1SHV-2+++++
S2SHV-7+++++
T1TEM-3+++++
T4TEM-10++++
T5TEM-50+++++
  • a −, negative; +, positive.

  • b NCCLS guidelines for screening for ESBL-producing bacteria. CPD, CAZ, and CTX were each used at 1 μg/ml.

  • c NCCLS guidelines for ESBL disk confirmation tests.

  • d PCR primers for CTX-M groups (refer to Materials and Methods for details). Group I includes CTX-M-1, -3, -10 to -12, -15 (UOE-1), -22, -23, -28, -29, and -30. Group II includes CTX-M-2, -4 to -7, and -20 and Toho-1. Group III includes CTX-M-8. Group IV includes CTX-M-9, -13, -14, -16 to -19, -21, and -27 and Toho-2. Finally, group V includes CTX-M-25 and -26.