Abstract
<title>Abstract</title> <p> Background Antimicrobial resistance (AMR) is a threat to human health. Children represent one of the most vulnerable populations affected by AMR. Sepsis causes substantial mortality in children worldwide. The incidence and mortality rates of sepsis in neonates are particularly high. This study aimed to determine the drug susceptibility of bacterial isolates causing bloodstream infections in children in Myanmar. Methods From August 2023 to July 2025, 4,263 blood samples were collected from children (aged birth–13 yrs old; median age: 228 days) at Yangon Children’s Hospital. Among 765 culture-positive samples, 160 isolates of <italic>Acinetobacter baumannii</italic> , <italic>Escherichia coli</italic> , <italic>Klebsiella pneumoniae</italic> , <italic>Staphylococcus aureus</italic> , and <italic>Salmonella</italic> spp. were identified using biochemical methods and matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS). Drug susceptibility was tested according to the Global Antimicrobial Resistance and Use Surveillance System (GLASS) protocols using the disk diffusion and broth microdilution methods. Gram-negative isolates were further tested for NDM metallo-β-lactamase (MBL) production using an imunochromatographic test (ICT). Results Of the 160 isolates, <italic>K. pneumoniae</italic> was the most prevalent (53.1%), followed by <italic>S. aureus</italic> (16.3%), <italic>Salmonella</italic> Typhi/Paratyphi A (15.6%), <italic>E. coli</italic> (8.1%), and <italic>A. baumannii</italic> (6.9%). Overall, 82.5% were resistant to at least one antibiotic included in the GLASS protocols: 96.5% of <italic>K. pneumoniae</italic> isolates, 96.0% of <italic>S</italic> . Typhi/Paratyphi A, 92.3% of <italic>E. coli</italic> , 45.5% of <italic>A. baumannii</italic> , and 38.5% of <italic>S. aureus</italic> were drug-resistant. Meropenem resistance was found in 72.9% of <italic>K. pneumoniae</italic> and 38.5% of <italic>E. coli</italic> isolates. The ICT kit revealed that 48.5% of 143 Gram-negative isolates and 92% of 71 meropenem-resistant Gram-negative isolates produced NDM-MBL. Conclusions This study highlights a high prevalence of antimicrobial resistance and NDM-MBL production among Gram-negative pathogens causing bloodstream infections in children in Myanmar, and demonstrates that rapid diagnostic tools such as ICT kits could be valuable for guiding treatment decisions and infection control. </p>