The Evolution of Antimicrobial Resistance in Mexico During the Last Decade: Results from the INVIFAR Group

<b><i>Background:</i></b> Surveillance of antimicrobial resistance (AMR) requires an international approach with national and local strategies. Our aim was to summarize a retrospective 10-year report of antibiotic resistance of gram-positive and gram-negative bacteria in Mexico. <b><i>Methods:</i></b> A total of 46 centers from 22 states of Mexico participated. Databases of AMR from January 2009 to December 2018 were included for most species. The 10-year period was divided into five 2-year periods. <b><i>Results:</i></b> For <i>Staphylococcus aureus,</i> a decrease in resistance in all specimens was observed for erythromycin and oxacillin (<i>p</i> < 0.0001 for each). For <i>Enterobacter</i> spp., resistance to meropenem increased for urine specimens (<i>p</i> = 0.0042). For <i>Klebsiella</i> spp., increased drug resistance in specimens collected from blood was observed for trimethoprim/sulfamethoxazole, gentamicin, tobramycin (<i>p</i> < 0.0001 for each), meropenem (<i>p</i> = 0.0014), and aztreonam (<i>p</i> = 0.0030). For <i>Acinetobacter baumannii</i> complex, high drug resistance was detected for almost all antibiotics, including carbapenems, except for tobramycin, which showed decreased resistance for urine, respiratory, and blood isolates (<i>p</i> < 0.0001 for each), and for amikacin, which showed a decrease in resistance in urine specimens (<i>p</i> = 0.0002). An increase in resistance to cefepime was found for urine, respiratory, and blood specimens (<i>p</i> < 0.0001 for each). For <i>Pseudomonas aeruginosa</i>, aztreonam resistance increased for isolates recovered from blood (<i>p</i> = 0.0001). <b><i>Conclusion:</i></b> This laboratory-based surveillance of antibiotic resistance shows that resistance is increasing for some antibiotics in different bacterial species in Mexico and highlights the need for continuous monitoring of antibiotic resistance.