Antimicrobial Susceptibility Among Gram-Negative Isolates in Pediatric Patients in Latin America, Africa-Middle East, and Asia From 2016-2020 Compared to 2011-2015: Results From the ATLAS Surveillance Study.

Antimicrobial resistance (AMR) data in the pediatric population are limited, particularly in developing countries. This study assessed the AMR profile and key resistance phenotypes and genotypes for Gram-negative bacteria (GNB) isolates collected as part of the Antimicrobial Testing Leadership and Surveillance program from pediatric patients in Latin America, Africa-Middle East, and Asia in 2016-2020 versus 2011-2015. Minimum inhibitory concentrations by broth microdilution methodology were interpreted per the Clinical and Laboratory Standards Institute. European Committee on Antimicrobial Susceptibility Testing breakpoints were used for interpreting colistin activity. β-lactamase genes were screened by polymerase chain reaction and sequencing. For Acinetobacter baumannii, low susceptibility (<60.0%) was observed for all antimicrobials, except colistin (≥92.9%), across regions and year periods. Ceftazidime-avibactam, amikacin, colistin, and meropenem were mostly active (78.6%-100.0%) against Enterobacter cloacae, Escherichia coli, and Klebsiella pneumoniae. For Pseudomonas aeruginosa, susceptibility to ceftazidime-avibactam, amikacin, and colistin was ≥85.9%. Among resistance phenotypes, carbapenem-resistant (CR, ≥44.8%) and difficult-to-treat resistant (DTR, ≥37.1%) rates were the highest in A. baumannii. A consistent increase in CR and DTR K. pneumoniae was noted across regions over time. Extended-spectrum β-lactamases (ESBL)-producing K. pneumoniae (32.6%-55.6%) were more frequent than ESBL-producing E. coli (25.3%-37.1%). CTX-M was the dominant ESBL among Enterobacterales. NDM-positive Enterobacterales species and VIM-positive P. aeruginosa were identified across regions. This study identified high susceptibility to few agents for key GNB in pediatric patients. Continued surveillance of resistance phenotypes and genotypes at regional levels may help to guide appropriate treatment decisions.