61 Antibiotic Resistant Patterns of Bacterial Pathogens Causing Invasive Neonatal Infections in Northern Alberta

Abstract

Abstract Background Antimicrobial resistance is one of the most serious global health threats facing the world today. The neonatal intensive care unit (NICU) is a clinical environment that houses newborn infants who are highly susceptible to overwhelming infection. Early and decisive treatment with powerful anti-microbials tends to be the preferred clinical choice for treating sick infants empirically. Prolonged exposure to antimicrobials can result in multi-drug resistant organisms (MDROs), which can be associated with mortality due to an increase in virulence, delay in appropriate treatment, and a lack of treatment options. An updated antibiogram is important for determining the optimal empirical antimicrobial choice for sepsis evaluations. There is currently a lack of antimicrobial susceptibility data for bacterial pathogens in the Northern Alberta region. Objectives The objective of this study is to understand the antibiotic resistance patterns among isolates responsible for bacteremia and meningitis in the NICUs in Northern Alberta through the standard antibiograms produced by microbiology laboratories. Design/Methods We conducted a retrospective study to analyze antimicrobial resistance patterns found in NICUs during 2013-2021 in Northern Alberta. Bacteria isolated from blood and cerebrospinal fluid according to commonly used antibiotics in NICUs were collated to create a provincial antibiogram. Results A total of 5562 isolates were included in this antibiogram. The most frequently isolated organisms were Escherichia coli (1521), Staphylococcus aureus (1157), members of coagulase-negative staphylococcus (534), Enterococcus faecalis (326), and Klebsiella pneumoniae (357) in neonatal populations. Among the 1157 S. aureus isolates, 24% were resistant to oxacillin (i.e., “methicillin-resistant S. aureus” or MRSA) and 1% were resistant to vancomycin (i.e., “vancomycin-resistant S. aureus” or VRSA). Of the 326 strains of Enterococcus spp., there were no vancomycin-resistant enterococci (VRE) identified. Among gram-negative isolates, 251 out of the 2690 (9.6%) were producing extended-spectrum beta-lactamase (ESBL), in which 52% and 94% were susceptible to gentamicin and amikacin respectively. Among the non-ESBL-producing isolates, E. coli (1521) and K. pneumoniae (357), 7% of the E. coli strains and 1% of the K. pneumoniae strains were resistant to gentamicin. Conclusion The provincial antibiogram is a useful clinical tool that can best inform clinicians on the appropriate choice of empirical antimicrobial agent based on commonly identified invasive pathogens in neonatal infections within Northern Alberta. Our findings on these resistant patterns can aid next steps for developing an antimicrobial stewardship program.