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Carbapenem-resistant Acinetobacter baumannii (CRAB) appeared more frequently in children and caused a great threat to global public health. It is urgent to investigate the carbapenem resistance and virulence of CRAB for clinicians to choose appropriate antibiotics. A retrospective study of 77 nonduplicated CRAB isolates was conducted. The carbapenem resistance and virulence genes were characterized by polymerase chain reaction (PCR) and gel electrophoresis. In the present study, A. baumannii mainly came from the intensive care unit and was mostly isolated from sputum samples. The carbapenem resistant rate of A. baumannii in 2018–2020 increased significantly compared with that in 2016–2017. All isolates had carbapenem resistant genes. They were highly resistant to a variety of antibiotics but were relatively sensitive to fluoroquinolones and tetracyclines. blaVIM and blaOXA-23 were detected in all isolates, whereas blaOXA-51, blaIMP and blaNDM were present in 98.70%, 67.53% and 31.17% of isolates, respectively. Notably, 1 isolate A. baumannii was identified as multidrug-resistant A. baumannii (MDR-AB), and 76 other extensively drug-resistance (XDR) isolates were also detected. Virulence genes were present in 100% of all isolates, including genes in the iron acquisition system (basJ), secretion systems (ompA, plcD), quorum sensing system (abaI) and biofilm formation (csuA). adeH, pgaA, and ptk were present in 98.70%, 98.70% and 94.80% of isolates, respectively. CRAB, which is prevalent in east China, carries a large number of drug resistance and virulence genes. Fluoroquinolones and tetracyclines may be effective antibiotics for the treatment of CRAB infection in children. An in-depth understanding of the resistance and virulence of CRAB is conducive to timely guiding empirical drug use and controlling infection. [ABSTRACT FROM AUTHOR]

Introduction: To analyze the pathogen distribution and drug resistance of newborns with bloodstream infection (BSI) to help clinicians choose the appropriate empirical antibiotic therapy for clinical infection control. Methods: A total of 707 neonatal BSI cases were retrospectively analyzed. The bacteria in blood culture-positive samples were cultured, identified, and analyzed for drug sensitivity by routine methods. Statistical software was used to compare and analyze the basic data, pathogenic information, and drug resistance of the main bacteria. Results: The 5-year average positive rate of neonatal blood culture was 2.50%. The number of specimens submitted for inspection in 2020 significantly decreased. The top five infectious pathogens with the highest proportion were coagulase-negative Staphylococcus (67.35%), of which Staphylococcus epidermidis had the highest proportion (31.26%), followed by Escherichia coli (12.87%), Klebsiella pneumoniae (9.05%), Streptococcus agalactiae (8.63%), and Staphylococcus aureus (3.25%). Gram-positive (G+) bacteria were dominant, accounting for 69.45%. The main G+ bacteria had a higher rate of resistance to erythromycin and penicillin G. The main Gram-negative (G–) bacteria had a high resistance rate to a variety of antibacterial drugs, especially cephalosporin antibiotics. The overall resistance of K. pneumoniae was higher than that of E. coli. The top two fungi detected were Candida parapsilosis and Candida albicans. C. parapsilosis did not appear to be resistant to antibiotics, while C. albicans was resistant to multiple antibiotics. The type of microbial infection had a statistically significant difference in the positive rate among the age at delivery and wards (p < 0.05). There were significant differences in the detection of fungi among these groups (p < 0.05). The positive rate of G+ bacteria in the term newborns was significantly higher than that in the preterm newborns (p < 0.05). Preterm newborns are more susceptible to pneumonia. Conclusion: G+ bacteria are the main pathogens of neonatal BSI. Preterm newborns are more likely to be infected with G– bacteria. E. coli and K. pneumoniae are the most common G– bacteria, and both have a high resistance rate to a variety of antibacterial drugs. According to the distribution characteristics and drug resistance, it is very important to select antibiotics reasonably. [ABSTRACT FROM AUTHOR]