Table 1. Classification of the P. aeruginosa strains (origin, haplotype, susceptibility, MexAB-OprM phenotype, mexA transcript expression, and carbapenemase production).
| Antibiotics | SP | MexAB-OprM | Transcript expression | Carbapenemase | ||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ID | H | ST | GEN | TOB | AK | IMI | MEM | CAZ | CPM | P/T | AZT | CIP | LEV | CB* | FOS* | CS | CB—PaβN | CB + PaβN | a | mexA | b | S | M | |
| 18H | 1 | 1725 | S | S | S | S | S | S | S | I | R | I | S | R | R | S | MDR | 2048 | 256 | * | 0.05 | - | / | / |
| 54H | 1 | 1725 | R | R | R | R | R | R | R | R | R | R | R | R | R | S | XDR | 2048 | 1024 | - | 79.59 | + | - | - |
| 3H † | 1 | 1725 | R | R | R | R | R | R | R | I | R | R | R | R | R | R | XDR | 2048 | 1024 | - | 0.08 | - | - | - |
| 14H † | 1 | 1725 | R | R | I | R | R | R | R | I | R | R | R | R | R | S | XDR | 2048 | 1024 | - | 0.02 | - | - | - |
| 15H † | 1 | 1725 | R | R | R | R | R | R | R | I | R | R | R | R | R | S | XDR | 2048 | 512 | * | 0.03 | - | - | - |
| 39H | 1 | 1725 | R | R | R | S | R | I | R | R | R | R | S | R | R | R | XDR | 2048 | 512 | * | 0.64 | - | - | - |
| 55H | 1 | 1725 | R | R | R | R | R | R | R | I | R | R | R | R | R | R | XDR | 2048 | 512 | * | 4.31 | + | - | - |
| 8H | 1 | 1725 | R | R | R | R | R | R | R | I | R | R | R | R | R | R | XDR | 1024 | 64 | + | 37.31 | + | ND | ND |
| 53H | 1 | 1725 | R | R | R | R | R | R | R | R | R | R | R | R | R | S | XDR | 64 | 4 | - | 85.93 | + | - | - |
| 38H | 1 | 1725 | R | R | R | R | R | R | R | R | R | R | R | R | R | S | XDR | 2048 | 16 | + | 1.08 | - | - | - |
| 43H | 1 | 1725 | R | R | R | R | R | R | R | R | R | R | R | R | R | S | XDR | 2048 | 16 | + | 0.13 | - | - | - |
| 5H | 1 | 1725 | R | R | R | R | R | R | R | I | R | R | R | R | R | R | XDR | 2048 | 8 | + | 405.31 | + | ND | ND |
| 25H | 1 | 1725 | R | R | R | R | R | R | R | R | R | R | I | R | R | R | XDR | 2048 | 8 | + | 184.10 | + | - | - |
| 6H | 1 | 1725 | R | R | R | R | R | R | R | R | R | R | R | R | R | R | PDR | 2048 | 1024 | - | 0.17 | - | - | - |
| 7H | 1 | 1725 | R | R | R | R | R | R | R | R | R | R | R | R | R | R | PDR | 2048 | 1024 | - | 0.07 | - | - | - |
| 30H | 1 | 1725 | R | R | R | R | R | R | R | R | R | R | R | R | R | R | PDR | 2048 | 1024 | - | 1.66 | - | - | - |
| 31H | 1 | 1725 | R | R | R | R | R | R | R | R | R | R | R | R | R | R | PDR | 2048 | 1024 | - | 3.02 | + | - | - |
| 37H | 1 | 1725 | R | R | R | R | R | R | R | R | R | R | R | R | R | R | PDR | 1024 | 512 | - | 139.32 | + | - | - |
| 11H | 1 | 1725 | R | R | R | R | R | R | R | R | R | R | R | R | R | R | PDR | 2048 | 512 | * | 0.03 | - | - | - |
| 12H | 1 | 1725 | R | R | R | R | R | R | R | R | R | R | R | R | R | R | PDR | 2048 | 512 | * | 0.53 | - | - | - |
| 26H | 1 | 1725 | R | R | R | R | R | R | R | R | R | R | R | R | R | R | PDR | 2048 | 512 | * | 132.43 | + | - | - |
| 36H | 1 | 1725 | R | R | R | R | R | R | R | R | R | R | R | R | R | R | PDR | 1024 | 256 | * | 513.65 | + | - | - |
| 40H | 1 | 1725 | R | R | R | R | R | R | R | R | R | R | R | R | R | R | PDR | 2048 | 512 | * | 0.10 | - | - | - |
| 41H | 1 | 1725 | R | R | R | R | R | R | R | R | R | R | R | R | R | R | PDR | 1024 | 16 | + | 3.82 | + | - | - |
| 50H | 1 | 1725 | R | R | R | R | R | R | R | R | R | R | R | R | R | R | PDR | 2048 | 32 | + | 1.84 | - | - | - |
| 33H | 1 | 1725 | R | R | R | R | R | R | R | R | R | R | R | R | R | R | PDR | 2048 | 16 | + | 0.05 | - | - | - |
| 48H | 1 | 1725 | R | R | R | R | R | R | R | R | R | R | R | R | R | R | PDR | 2048 | 16 | + | 1.97 | - | + | - |
| 4H | 1 | 1725 | R | R | R | R | R | R | R | R | R | R | R | R | R | R | PDR | 2048 | 8 | + | 0.07 | - | ND | ND |
| 16H | 1 | 1725 | R | R | R | R | R | R | R | R | R | R | R | R | R | R | PDR | 2048 | 8 | + | 7.06 | + | - | - |
| 42H | 1 | 1725 | R | R | R | R | R | R | R | R | R | R | R | R | R | R | PDR | 2048 | 8 | + | 0.18 | - | - | - |
| 49H | 1 | 1725 | R | R | R | R | R | R | R | R | R | R | R | R | R | R | PDR | 1024 | 4 | + | 0.15 | - | ND | ND |
| 35H † | 1 | 1725 | R | R | R | R | R | R | R | R | R | R | R | R | R | R | PDR | 2048 | 4 | + | 0.35 | - | - | - |
| 51H | 1 | 1725 | R | R | R | R | R | R | R | R | R | R | R | R | R | R | PDR | 2048 | 4 | + | 0.26 | - | + | - |
| 46H | 1 | 2244 | R | R | S | R | R | R | R | R | R | R | R | R | R | R | XDR | 1024 | 1024 | - | 0.82 | - | + | - |
| 47H † | 1 | 2245 | R | R | R | R | R | R | R | I | R | R | R | R | R | R | XDR | 2048 | 32 | + | 6.40 | + | - | - |
| 52H | 1 | 2247 | R | R | R | R | R | R | R | R | R | R | R | R | R | S | XDR | 1024 | 4 | + | 1.00 | - | ND | ND |
| 45H | 1 | 2243 | R | R | R | R | R | R | R | R | R | R | R | R | R | R | PDR | 512 | 32 | + | 14.07 | + | ND | ND |
| 1H | 1 | 1723 | R | R | R | R | R | R | R | R | R | R | R | R | R | R | PDR | 2048 | 32 | + | 0.04 | - | - | - |
| 32H | 1 | 1730 | R | R | R | R | R | R | R | R | R | R | R | R | R | R | PDR | 2048 | 4 | + | 33.00 | + | ND | ND |
| 12A | 1 | 111 | S | S | S | S | I | S | S | S | S | I | S | R | R | R | MDR | 512 | 512 | - | 0.07 | - | / | / |
| 56H | 2 | 1725 | R | R | R | R | R | R | R | R | R | R | R | R | R | R | PDR | 512 | 4 | + | 4.66 | + | - | - |
| 44H | 3 | 2246 | R | R | R | R | R | R | R | I | R | R | R | R | R | R | XDR | 2048 | 512 | * | 0.15 | - | - | - |
| 10A | 4 | 2566 | S | S | S | S | I | S | R | S | S | S | S | R | R | R | MDR | 128 | 256 | - | 0.02 | - | / | / |
| 10H † | 5 | 1726 | R | R | R | R | R | R | R | R | R | R | R | R | R | S | XDR | 2048 | 512 | * | 8.79 | + | - | - |
| 27H † | 5 | 1727 | R | S | R | R | R | R | R | R | R | R | R | R | R | R | XDR | 2048 | 512 | * | 123.89 | + | - | - |
| 9H | 5 | 1724 | R | R | R | R | R | R | R | I | R | R | R | R | R | R | XDR | 2048 | 256 | * | 0.05 | - | - | - |
| 2H † | 5 | 1724 | R | R | R | R | R | R | R | I | R | R | R | R | R | S | XDR | 2048 | 128 | + | 0.15 | - | - | - |
| 28H † | 5 | 1728 | R | R | R | R | R | R | R | I | R | R | R | R | R | S | XDR | 2048 | 8 | + | 0.03 | - | - | - |
| 17H | 6 | 1733 | S | S | S | S | R | S | S | S | S | S | S | R | R | R | MDR | 2048 | 128 | + | 0.07 | - | ND | ND |
| 11A | 7 | 2567 | S | S | S | S | S | S | S | S | I | S | S | R | R | R | MDR | 256 | 256 | - | 1.01 | - | / | / |
| 68H | 8 | 2710 | R | R | R | R | R | R | R | I | R | R | R | R | R | R | XDR | 1024 | 512 | - | 2.65 | - | + | - |
| 70H | 8 | 2716 | R | R | R | R | R | R | R | I | R | R | R | R | R | R | XDR | 1024 | 512 | - | 97.90 | + | + | - |
| 63H | 8 | 2704 | R | R | R | R | R | R | R | I | R | R | R | R | R | R | XDR | 2048 | 512 | * | 316.39 | + | ND | ND |
| 67H | 8 | 2710 | R | R | R | R | R | R | R | R | R | R | R | R | R | R | PDR | 1024 | 512 | - | 1041.74 | + | + | - |
| 72H | 8 | 2731 | R | R | R | R | R | R | R | R | R | R | R | R | R | R | PDR | 2048 | 1024 | - | 8.81 | + | + | - |
| 69H | 9 | 2713 | R | R | R | R | R | R | R | I | R | R | R | R | R | R | XDR | 1024 | 512 | - | 2.13 | - | - | + |
| 73H | 10 | 2732 | S | S | S | R | R | S | I | I | R | R | R | R | R | R | MDR | 512 | 512 | - | 3.17 | + | - | - |
| 2A | 11 | 2249 | S | S | S | S | S | S | S | S | S | S | S | R | R | R | MDR | 128 | 128 | - | 0.48 | - | / | / |
| 9A | 11 | 2565 | S | S | S | S | R | S | S | S | I | R | I | R | R | R | MDR | 256 | 256 | - | 2.76 | - | - | - |
| 71H | 12 | 2559 | R | R | R | R | R | R | R | R | S | R | R | R | R | R | XDR | 1024 | 1024 | - | 231.70 | + | - | + |
| 65H | 12 | 233 | R | R | R | R | R | R | R | R | S | R | R | R | R | R | XDR | 2048 | 1024 | - | 1485.21 | + | - | + |
| 75H | 12 | 233 | R | R | R | R | R | R | R | I | S | R | R | R | R | R | XDR | 2048 | 1024 | - | 2.44 | - | - | + |
| 76H | 12 | 233 | R | R | R | R | R | R | R | R | S | R | R | R | R | R | XDR | 2048 | 1024 | - | 100.34 | + | ND | ND |
| 57H | 12 | 233 | R | R | R | R | R | R | R | R | S | R | R | R | R | R | XDR | 2048 | 512 | * | 127.01 | + | - | + |
| 59H | 12 | 233 | R | R | R | R | R | R | R | R | S | R | R | R | R | R | XDR | 2048 | 512 | * | 1.47 | - | - | + |
| 77H | 12 | 233 | R | R | R | R | R | R | R | R | S | R | R | R | R | R | XDR | 2048 | 512 | * | 44.75 | + | - | + |
| 74H | 12 | 2560 | R | R | R | R | R | R | R | R | I | R | R | R | R | R | XDR | 2048 | 1024 | - | 50.45 | + | - | + |
| 66H † | 12 | 2559 | R | R | R | R | R | R | R | R | S | R | R | R | R | R | XDR | 2048 | 1024 | - | 4.43 | + | - | + |
| 1A | 13 | 2561 | S | S | S | S | R | S | R | I | R | S | S | R | R | S | MDR | 512 | 512 | - | 0.83 | - | ND | ND |
| 23H | 14 | 1736 | S | S | S | S | S | S | S | S | I | I | I | R | R | R | MDR | 128 | 32 | * | 30.22 | + | / | / |
| 24H | 14 | 1736 | S | S | S | S | I | S | S | S | S | S | S | R | R | R | MDR | 128 | 16 | * | 9.74 | + | / | / |
| 61H † | 15 | 2557 | S | S | S | S | S | S | I | S | S | S | S | R | R | R | MDR | 2048 | 512 | * | 90.93 | + | / | / |
| 13A | 16 | 2568 | S | S | S | S | R | S | R | S | S | R | S | R | R | S | MDR | 128 | 256 | - | 8.30 | + | + | - |
| 64H | 17 | 2709 | R | R | S | R | S | R | S | I | I | S | R | R | R | R | XDR | 1024 | 256 | * | 89.14 | + | ND | ND |
| 60H † | 18 | 2248 | R | R | S | R | R | R | R | I | R | I | R | R | R | S | XDR | 2048 | 1024 | - | 167.88 | + | - | + |
| 62H | 18 | 2558 | I | S | R | R | R | R | R | I | R | I | R | R | R | S | XDR | 2048 | 1024 | - | 6.63 | + | - | + |
| 58H | 19 | 112 | R | R | R | I | R | R | R | S | S | S | S | R | R | R | MDR | 1024 | 32 | + | 4.23 | + | - | - |
| 22H | 20 | 1735 | S | S | S | S | S | S | S | S | S | S | S | R | R | R | MDR | 2048 | 256 | * | 0.55 | - | / | / |
| 34H † | 21 | 561 | S | S | S | S | S | S | S | S | S | S | S | R | R | R | MDR | 128 | 128 | - | 0.10 | - | / | / |
| 13H † | 21 | 1737 | S | S | S | S | S | S | S | S | S | S | S | R | R | R | MDR | 2048 | 1024 | - | 0.31 | - | / | / |
| 19H | 22 | 1731 | S | S | S | S | S | S | I | S | S | S | R | R | R | S | MDR | 256 | 32 | + | 1.48 | - | / | / |
| 4A | 23 | 2563 | S | S | S | R | R | S | S | S | R | S | S | R | R | R | MDR | 2048 | 1024 | - | 0.88 | - | ND | ND |
| 21H | 24 | 1734 | S | S | S | S | S | S | S | S | S | S | S | R | R | R | MDR | 512 | 128 | + | 7.00 | + | / | / |
| 3A | 25 | 2562 | S | S | S | R | S | S | S | S | S | S | S | R | R | R | MDR | 64 | 64 | - | 0.02 | - | ND | ND |
| 7A | 26 | 2250 | S | S | S | S | S | S | S | S | I | S | S | R | R | S | S | 64 | 128 | - | 0.04 | - | / | / |
| 6A | 26 | 540 | S | S | S | S | S | S | S | S | S | S | I | R | R | S | S | 128 | 128 | - | 0.03 | - | / | / |
| 8A | 26 | 2251 | S | S | S | S | I | S | S | S | S | R | S | R | R | R | MDR | 64 | 64 | - | 0.03 | - | / | / |
| 5A | 26 | 2564 | S | S | S | S | R | S | S | S | S | S | S | R | R | R | MDR | 128 | 128 | - | 16.73 | + | - | - |
| 29H † | 26 | 1729 | R | R | R | R | R | R | R | R | S | R | R | R | R | R | XDR | 2048 | 256 | * | 164.59 | + | - | - |
| 14A | 26 | 1729 | S | S | R | S | R | S | R | I | R | R | S | R | R | R | XDR | 64 | <8 | * | 1.95 | - | ND | ND |
| 20H † | 27 | 2226 | S | S | S | S | S | S | S | S | S | S | S | R | R | S | S | 1024 | 1024 | - | 0.07 | - | / | / |
| PAO1 | 549 | S | S | S | S | S | S | S | S | S | S | S | S | R | S | S | 64 | 64 | - | 1.00 | - | / | / | |
ID: origin (H: nosocomial strains; A: environmental strains); patient death outcome: †
H: Haplotype was considered as the DNA sequence from the concatenation of mexR-nalC-nalD genes.
ST: Sequence Type. The ST1725 (most frequent) and the ST233 (high risk clone) are highlighted.
Antibiotic categories: Aminoglycosides (GEN: gentamicin, TOB: tobramycin, AK: amikacin), Carbapenems (IMI: imipenem, MEM: meropenem), Cephalosporins (CAZ: ceftazidime, CPM: cefepime), Penicillins (CB: carbenicillin), Penicillins + β-lactamase inhibitors (P/T: piperacillin-tazobactam), Monobactams (AZT: aztreonam), Fluoroquinolones (CIP: ciprofloxacin, LEV: levofloxacin), Phosphonic Acids (FOS: fosfomycin), Polymyxins (CS: colistin).
SP: Susceptibility: S: sensitive, I: intermediate resistant, R: resistant; S: sensitive; MDR: multidrug resistant, XDR: extensively drug resistant, PDR (highlighted): pan drug resistant.
MexAB-OprM: MexAB-OprM efflux pump phenotypic detection; carbenicillin (CB), a substrate of the pump, was used as reporter antibiotic; CB—PaβN: MIC determined for each strain to CB in the absence of the efflux inhibitor Phe-Arg-β-naphthylamine (PaβN) (50 μg/mL); CB + PaβN: MIC determined for each strain to CB in the presence of the efflux inhibitor PaβN (50 μg/mLg/L); a: Elevation of the MIC is caused by the MexAB-OprM efflux pump: +: MexAB-OprM efflux pump is most likely the cause of the elevation of the MIC (values in bold); *: MexAB-OprM efflux pump is contributing in the elevation of the MIC (values in italics); -: MexAB-OprM efflux pump is unlikely to be the cause of the elevation of the MIC or no elevation of the MIC (underlined values).
Transcript expression: mexA: transcript expression level; transcript ratio between the target gene mexA and the reference gene rpsL; b: +: mexAB-oprM overtranscription; -: mexAB-oprM basal level.
Carbapenemase: S: serine carbapenemase, M: metallo-β-lactamase, +: presence of carbapenemase; ND: not determined; /: meropenem and imipenem sensitive strain; Carbapenemase-producing test was developed in meropenem and/or imipenem resistant strains.