Table 1.
In vitro activity of ceftazidime-avibactam and comparator agents against Enterobacterales isolates collected in the Latin American region as part of the ATLAS global surveillance program from 2017 to 2019.
| Antimicrobial agent | MIC (µg/ml) |
Interpretation (CLSI) |
||||
|---|---|---|---|---|---|---|
| Organism, phenotype/genotype (no. of isolates) | MIC50 | MIC90 | % Susceptible | % Intermediate | % Resistant | |
| Latin America, All Enterobacterales (8416)a | Ceftazidime-avibactam | 0.12 | 0.5 | 98.1 | NA | 1.9 |
| Ceftazidime | 0.25 | 64 | 67.8 | 3.6 | 28.5 | |
| Cefepime | ≤0.12 | >16 | 68.5 | 6.7 | 24.7 | |
| Piperacillin-tazobactam | 2 | >64 | 82.7 | 5.4 | 11.9 | |
| Meropenem | ≤0.06 | 0.12 | 93.2 | 0.8 | 6.0 | |
| Levofloxacin (n = 8415)d | ≤0.25 | >8 | 61.0 | 5.6 | 33.4 | |
| Amikacin | 2 | 8 | 96.2 | 1.5 | 2.3 | |
| Colistin | 0.5 | >8 | NA | 81.1 | 18.9 | |
| Tigecycline | 0.5 | 1 | 97.2 | 2.4 | 0.4 | |
| Meropenem-NS (570)b | Ceftazidime-avibactam | 1 | >128 | 74.7 | NA | 25.3 |
| Ceftazidime | 128 | >128 | 5.4 | 3.9 | 90.7 | |
| Cefepime | >16 | >16 | 3.7 | 7.7 | 88.6 | |
| Piperacillin-tazobactam | >64 | >64 | 1.9 | 5.6 | 92.5 | |
| Meropenem | >8 | >8 | 0 | 11.6 | 88.4 | |
| Levofloxacin | >8 | >8 | 16.0 | 8.4 | 75.6 | |
| Amikacin | 8 | >32 | 70.2 | 10.4 | 19.5 | |
| Colistin | 0.5 | >8 | NA | 78.2 | 21.8 | |
| Tigecycline | 0.5 | 2 | 95.6 | 4.0 | 0.4 | |
| Meropenem-NS, MBL-, carbapenemase+ (358) | Ceftazidime-avibactam | 1 | 2 | 99.4 | NA | 0.6 |
| Ceftazidime | 64 | >128 | 5.3 | 5.6 | 89.1 | |
| Cefepime | >16 | >16 | 4.5 | 8.4 | 87.2 | |
| Piperacillin-tazobactam | >64 | >64 | 0 | 3.4 | 96.6 | |
| Meropenem | >8 | >8 | 0 | 7.0 | 93.0 | |
| Levofloxacin | >8 | >8 | 14.2 | 5.0 | 80.7 | |
| Amikacin | 4 | >32 | 76.5 | 13.1 | 10.3 | |
| Colistin | 0.5 | >8 | NA | 74.9 | 25.1 | |
| Tigecycline | 0.5 | 2 | 98.0 | 1.7 | 0.3 | |
| Meropenem-NS, MBL-, carbapenemase- (72) | Ceftazidime-avibactam | 1 | 4 | 95.8 | NA | 4.2 |
| Ceftazidime | 64 | >128 | 16.7 | 2.8 | 80.6 | |
| Cefepime | >16 | >16 | 6.9 | 8.3 | 84.7 | |
| Piperacillin-tazobactam | >64 | >64 | 11.1 | 15.3 | 73.6 | |
| Meropenem | 2 | >8 | 0 | 52.8 | 47.2 | |
| Levofloxacin | >8 | >8 | 19.4 | 9.7 | 70.8 | |
| Amikacin | 4 | >32 | 81.9 | 2.8 | 15.3 | |
| Colistin | 0.5 | >8 | NA | 87.5 | 12.5 | |
| Tigecycline | 0.5 | 2 | 91.7 | 8.3 | 0 | |
| Multidrug-resistant (1773)c | Ceftazidime-avibactam | 0.5 | 4 | 91.8 | NA | 8.2 |
| Ceftazidime | 64 | >128 | 5.4 | 4.7 | 89.9 | |
| Cefepime | >16 | >16 | 1.6 | 3.6 | 94.8 | |
| Piperacillin-tazobactam | 32 | >64 | 44.3 | 11.1 | 44.6 | |
| Meropenem | ≤0.06 | >8 | 69.4 | 2.6 | 28.0 | |
| Levofloxacin (n = 1772)d | >8 | >8 | 7.1 | 4.3 | 88.5 | |
| Amikacin | 4 | >32 | 84.2 | 5.5 | 10.3 | |
| Colistin | 0.5 | >8 | NA | 85.4 | 14.6 | |
| Tigecycline | 0.5 | 2 | 95.8 | 3.5 | 0.7 | |
Abbreviations: NS, non-susceptible; MBL-, no gene encoding a metallo-β-lactamase was detected by PCR; carbapenemase+/-, a gene encoding a serine carbapenemase was (+) or was not (-) detected by PCR; multidrug-resistant, isolates resistant to three or more sentinel agents from different antimicrobial classes; NA, no breakpoint available.
All Enterobacterales were composed of Citrobacter amalonaticus (n = 10), Citrobacter braakii (n = 20), Citrobacter farmeri (n = 7), Citrobacter freundii (n = 251), Citrobacter koseri (n = 119), Citrobacter sedlakii (n = 6), Citrobacter youngae (n = 1), Citrobacter sp. (n = 4), Enterobacter asburiae (n = 87), Enterobacter bugandensis (n = 8), Enterobacter cloacae (n = 703), Enterobacter cloacae complex (n = 25), Enterobacter kobei (n = 27), Enterobacter ludwigii (n = 4), Enterobacter xiangfangensis (n = 14), Enterobacter sp. (n = 32), Escherichia coli (n = 2747), Klebsiella aerogenes (n = 221), Klebsiella oxytoca (n = 213), Klebsiella pneumoniae (n = 2441), Klebsiella variicola (n = 98), Morganella morganii (n = 263), Pantoea agglomerans (n = 1), Pantoea septica (n = 1), Proteus hauseri (n = 48), Proteus mirabilis (n = 436), Proteus penneri (n = 8), Proteus vulgaris (n = 58), Proteus sp. (n = 2), Providencia alcalifaciens (n = 4), Providencia rettgeri (n = 51), Providencia stuartii (n = 83), Providencia sp. (n = 2), Raoultella ornithinolytica (n = 17), Raoultella planticola (n = 2), Raoultella terrigena (n = 1), Salmonella sp. (n = 1), Serratia liquefaciens (n = 3), Serratia marcescens (n = 392), Serratia rubidaea (n = 1), Serratia ureilytica (n = 2), and Serratia sp. (n = 2).
One meropenem-nonsusceptible isolate collected in Guatemala was not molecularly characterized for β-lactamase genes.
Multidrug resistant Enterobacterales were composed of Citrobacter freundii (n = 15), Citrobacter koseri (n = 2), Enterobacter asburiae (n = 11), Enterobacter cloacae (n = 123), Enterobacter cloacae complex (n = 2), Enterobacter xiangfangensis (n = 1), Enterobacter sp. (n = 2), Escherichia coli (n = 605), Klebsiella aerogenes (n = 12), Klebsiella oxytoca (n = 14), Klebsiella pneumoniae (n = 845), Klebsiella variicola (n = 5), Morganella morganii (n = 18), Proteus mirabilis (n = 39), Providencia rettgeri (n = 7), Providencia stuartii (n = 17), Raoultella ornithinolytica (n = 1), Salmonella sp. (n = 1), and Serratia marcescens (n = 53).
Excluded one isolate of Salmonella sp.