Clinical outcomes and multidrug resistance patterns of rare Gram-negative bloodstream infections: An 8-year analysis from a tertiary pediatric hospital

Abstract

Objective: To evaluate the clinical characteristics, risk factors, antimicrobial susceptibility profiles, and outcomes of bloodstream infections caused by rare Gram-negative bacteria in a tertiary pediatric center.Methods: A retrospective analysis was conducted on pediatric patients (0-18 years) with rare Gram-negative bloodstream infections growth in blood cultures between 2016 and 2023. Common pathogens (Escherichia coli, Klebsiella pneumoniae, Pseudomonas spp., and Acinetobacter spp.) were excluded to focus on unusual isolates.Results: A total of 394 patients were included in the study. Their median age was 21.5 months and 237 (60.2%) were male. The cohort had a high prevalence of chronic underlying diseases (94.0%) and a median hospital stay of 27 (16, 49) days. Central venous catheters (35.8%) and recent blood product transfusions (35.8%) were the most frequent predisposing factors. The most prevalent isolates were Serratia spp. (20.1%), Stenotrophomonas maltophilia (17.5%), and Enterobacter spp. (15.2%). High rates of intrinsic and acquired resistance were observed: 100% of Serratia isolates were resistant to trimethoprim/sulfamethoxazole, and Elizabethkingia meningoseptica demonstrated extensive carbapenem resistance. Resistance to co- trimoxazole in Stenotrophomonas maltophilia was 0%. All-cause mortality was 13.7%, whereas infection-related mortality was 1.1%, specifically associated with Aeromonas spp. (10.0%), Comamonas testosteroni (25.0%), and Enterobacter spp (3.3%).Conclusions: Rare Gram-negative bacteria bloodstream infections in children represent a significant diagnostic and therapeutic challenge due to unpredictable resistance patterns. Our data suggest that empirical therapy for high-risk pediatric patients should be periodically reviewed to include coverage for these emerging pathogens, especially in those with indwelling devices and chronic comorbidities.

Keywords

Rare Gram-negative bacteremia / Children / Resistance / Pediatric bloodstream infections

Conflicting interest statement

The authors declare that they have no conflict of interest.

Funding

The authors declare that no funds, grants, or other support were received during the preparation of this manuscript.

Authors’ contributions

F.K. contributed to the conception, design, literature search, data analysis, statistical analysis, manuscript preparation and review. Ü.Ç. participated in the study design and manuscript editing. D.A. was responsible for the definition of intellectual content. Ö.Ö.G. conducted the literature search. F.T.Ç. acquired the experimental data. A.Ü. and N.N.T assisted in manuscript preparation.

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Edited by Pan Y, Lei Y, Zhang Q

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