Factors influencing antimicrobial resistance and outcome of Gram-negative bloodstream infections in children

Abstract

OBJECTIVE: The aim of this study was to collect data about pediatric Gram-negative bloodstream infections (BSI) to determine the factors that influence multidrug resistance (MDR), clinical course and outcome of children affected by Gram-negative sepsis. METHODS: In this observational, prospective, multicenter study we collected cases of pediatric Gram-negative BSI during a 2-year period. We analyzed epidemiological, microbiological and clinical factors that associated with acquisition of MDR infections and outcome. RESULTS: One-hundred and thirty-five BSI episodes were analyzed. Median age of children was 0.5 years (IQR 0.1-6.17, range 0-17 years). Predominant bacteria were Enterobacteriaceae (68.3 %), and Pseudomonas spp. (17.9 %). Multidrug resistance was detected in 45/134 cases (33.6 %), with the highest rates in Escherichia coli, Enterobacter and Pseudomonas spp. Acquisition of MDR pathogens was significantly associated with prior cephalosporin treatment, older age, admission to hemato-oncology unit, polymicrobial infections, higher rate of development of septic shock, and multiple organ failures. All-cause mortality was 17.9 %. Presence of septic shock at presentation and parenteral nutrition were associated with higher mortality. Pseudomonas spp., and Enterobacter spp. BSIs had the highest rate of mortality. Inappropriate empiric antibiotic therapy was more frequent in MDR patients, although not significantly associated with poor outcome. CONCLUSION: Rates of multidrug resistance and mortality in children with Gram-negative bloodstream infections remain high in our settings. Empiric broad-spectrum antibiotics and combination therapy could be recommended, especially in children with malignant diseases, patients admitted to the PICU, and for cases with septic shock, who have higher mortality risk.