Frequency and antimicrobial susceptibility of bacteria causing bloodstream infections in pediatric patients from United States (US) medical centers (2014-2018): therapeutic options for multidrug-resistant bacteria.

Studies evaluating large series of pediatric patients with bloodstream infections (BSIs) are scarce. We evaluated the frequency and antimicrobial susceptibility of organisms isolated from pediatric patients with BSI and therapeutic options for BSI caused by multidrug-resistant (MDR) organisms. A total of 2423 organisms were consecutively collected from 33 US medical centers between 2014 and 2018, and susceptibility was tested by reference broth microdilution methods. Isolates with an extended-spectrum β-lactamase phenotype were screened for β-lactamase genes. Overall, 40.2% of organisms were Gram-negative bacteria, 57.0% Gram-positives, and 2.8% Candida spp. The 5 most common organisms were Staphylococcus aureus (26.0%), Escherichia coli (13.0%), coagulase-negative staphylococci (8.3%), Enterococcus faecalis (7.1%), and Klebsiella pneumoniae (6.9%). Among S. aureus, 26.0% were oxacillin-resistant and 99.8% were susceptible to ceftaroline (MIC50/90, 0.25/0.5 mg/L). Enterobacterales and Pseudomonas aeruginosa isolates combined represented >85% of Gram-negative bacteria, and all isolates (100.0%) were susceptible to ceftazidime-avibactam.