TABLE 5.
Phenotypic and genotypic characteristics of 119 E. coli CTX-M producer strains
| Antimicrobial resistance patterna | pI(s)b | Genotype by PCR (gene type by sequencing)c:
|
PFGE profiled (no. of strains) | Hospital code | Total no. of strains | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| blaTEM | blaCTX-M | blaOXA | ISEcp1 | IS26 | IS903 | |||||
| AM A/S AT CF CT FX TX TZ XM KZ PM PI P/T TI CI NX OF AK GM TO | 5.4; 7.4; 8.9 | + (1b) | + (15) | + (30) | + | − | − | 0010 | A | 1 |
| AM A/S A/C AT CF CT TX TZ XM KZ PM PI P/T TI CI NX OF GM TO | 7.4; 8.9 | − | + (15) | + (30) | + | − | − | 0010 | D | 2 |
| AM A/S A/C AT CF CT TX TZ XM KZ PM PI P/T TI CI NX OF AK TO | 5.4; 7.4; 8.9 | + (1b) | + (15) | + (30) | + | − | − | 0006 | E | 1 |
| AM A/S AT CF CT TX TZ XM KZ PM PI P/T TI CI NX OF AK GM TO | 5.4; 7.4; 8.9 | + (1b) | + (15) | + (30) | + | − | − | 0010 | C | 1 |
| AM A/S AT CF CT TX TZ XM KZ PM PI P/T TI CI NX OF GM TO T/S | 5.4; 7.4; 8.9 | + (1b) | + (15) | + (30) | + | − | − | 0010 | C | 1 |
| AM A/S AT CF CT TX TZ XM KZ PM PI TI CI NX OF AK GM TO T/S | 5.4; 7.4; 8.9 | + (1b) | + (15) | + (30) | + | − | − | 0010 | B | 1 |
| AM A/S AT CF CT TX TZ XM KZ PM PI P/T TI CI NX OF GM TO | 5.4; 7.4; 8.9 | + (1b) | + (15) | + (30) | + | − | − | 0010 | C | 1 |
| AM A/S AT CF CT TX TZ XM KZ PM PI TI CI NX OF GM TO T/S | 5.4; 7.4; 8.9 | + (1b) | + (15) | + (30) | + | − | − | 0009 (1), | A, B, C, D, E, F, H | 19 |
| 0010 (13), 0012 (1), | ||||||||||
| 0013 (1), 0015 (1), 0017 (1), ND (1) | ||||||||||
| 5.4; 7.4; 8.9 | + (1)e | + (15) | + (30) | + | − | − | 0010 | C | 1 | |
| 5.4; 8.9 | + (1b) | + (32) | − | + | − | − | 0019 | E | 1 | |
| 5.4; 8.9 | + (1b) | + (15) | − | + | − | − | 0019 | E | 1 | |
| AM A/S AT CF CT TX TZ XM KZ PM PI TI CI NX OF GM TO | 8.1 | − | + (14) | − | + | − | − | 0005 | C | 1 |
| 7.4; 8.9 | − | + (15) | + (30) | + | − | − | 0007 (1), 0010 (3) | B, D, H | 4 | |
| 5.4; 7.4; 8.9 | + (1b) | + (15) | + (30) | + | − | − | 0016 (1), 0009 (2), | A, B, C, D, E, G, H, I | 52 | |
| 0010 (48), 0011 (1) | ||||||||||
| 5.4; 7.4; 8.9 | + (1a) | + (15) | + (30) | + | − | − | 0010 | H | 1 | |
| AM A/S AT CF CT TX TZ XM KZ PM PI TI CI NX OF TO T/S | 5.4; 7.4; 8.9 | + (1b) | + (15) | + (30) | + | − | − | 0010 | I | 1 |
| AM A/S AT CF CT TX TZ XM KZ PM PI TI CI NX OF GM | 5.4; 8.9f | + (1b) | + (15) | + (30) | + | − | − | 0010 | A | 1 |
| AM A/S AT CF CT TX TZ XM KZ PM PI TI CI NX OF TO | 7.4; 8.9 | − | + (15) | + (30) | + | − | − | 0010 | D, E | 3 |
| 5.4; 8.9 | + (1b) | + (15) | − | + | − | − | 0010 | D | 1 | |
| 5.4; 7.4; 8.9 | + (1b) | + (15) | + (30) | + | − | − | 0006 (2), 0008 (1), 0010 (7) | C, D, E, I | 10 | |
| AM A/S AT CF CT TX TZ XM KZ PM PI TI CI NX OF T/S | 5.4; 8.9 | + (1b) | + (15) | − | + | − | − | 0010 | A | 2 |
| AM AT CF CT TX TZ XM KZ PM PI TI CI NX OF TO | 7.4; 8.9 | − | + (15) | + (30) | + | − | − | 0010 | E | 1 |
| AM A/S AT CF CT TX TZ XM KZ PM PI TI CI NX OFg | 5.4; 8.9 | + (1b) | + (15) | − | + | − | − | 0006(1), 0010 (1) | E | 2 |
| AM A/S CF CT TX XM KZ PI TI CI NX OF GM TO T/S | 5.4; 8.1 | + (1b) | + (14) | − | + | − | + | 0001 | E | 1 |
| AM A/S CF CT TX XM KZ PI TI CI NX OF T/S | 5.4; 8.1 | + (1b) | + (14) | − | + | − | − | ND | C | 1 |
| AM A/S AT CF CT TX XM KZ PM PI TI T/Sg | 5.4; 8.9 | + (1b) | + (15) | − | + | − | − | 0004 | E | 1 |
| AM A/S CF CT TX XM KZ PM PI TI T/Sg | 5.4; 8.1 | + (1b) | + (14) | − | + | − | − | 0018 | C | 1 |
| AM A/S CF CT TX XM KZ PM PI TIg | 8.1 | − | + (14) | − | + | − | − | 0002 (1), 0003 (2), ND (1) | C, D, I | 4 |
| 5.4; 8.1 | + (1c) | + (14) | − | + | − | − | 0014 | D | 1 | |
| AM AT CF TX XM KZ PI TIg | 5.4; 8.9 | + (1b) | + (15) | − | + | − | − | 0010 | E | 1 |
AM, ampicillin; A/S, ampicillin-sulbactam; A/C, amoxicillin-clavulanic acid; AT, aztreonam; CF, cephalothin; FX, cefoxitin; CT, cefotaxime; TX, ceftriaxone; TZ, ceftazidime; XM, cefuroxime; KZ, cefazolin; PM, cefepime; PI, piperacillin; P/T, piperacillin-tazobactam; TI, ticarcillin; CI, ciprofloxacin; NX, norfloxacin; OF, ofloxacin; AK, amikacin; GM, gentamicin; TO, tobramycin; T/S, trimethoprim-sulfamethoxazole.
pIs were determined by IEF: 5.4 corresponds to TEM-1A, TEM-1B, or TEM-1C enzyme production; 7.4 corresponds to OXA-30 production; 8.1 corresponds to CTX-M-14; and 8.9 corresponds to CTX-M-15 or CTX-M-32 enzyme production.
blaTEM genes amplified by PCR were identified by sequencing as blaTEM-1A, blaTEM-1B, or blaTEM-1C; blaCTX-M genes were identified by sequencing as blaCTX-M-14, blaCTX-M-15, or blaCTX-M-32; and blaOXA genes were identified by sequencing as blaOXA-30. +, Amplification by PCR; −, no amplification by PCR.
PFGE profile and number of strains with each profile, deduced from the dendrogram presented on Fig. 1. ND, not determined.
More than one blaTEM-1 was present.
β-Lactamase with pI 7.4, corresponding to OXA-30 enzyme production, was not detected by IEF.
Non-multidrug-resistant pattern.