Antibiotic Resistance Patterns and Distribution of Microorganisms Identified in Blood Cultures from Pediatric Patients

Aim: The incidence of bacteremia caused by multidrug-resistantbacteria is increasing worldwide. Identifying the causativeagents of these infections and initiating appropriate antibiotictherapy early are crucial. This study aims to contribute to thedetermination of the etiology of bacteremia and sepsis and toguide the development of effective treatment strategies basedon the collected data.Material and Method: Patients with positive blood culture resultsbetween 2010 and 2021 in a university hospital were analyzedin terms of pathogen diversity and antibiotic resistance. Bloodculture data, including patient information, bacterial isolates, andantibiograms, were electronically retrieved from hospital records.Patients’ age, sex, and CRP levels were recorded. Categoricalvariables were presented as counts and percentages.Results: Of the 4711 blood cultures obtained from the PediatricClinic, 736 (15.6%) showed bacterial growth. The mean ageof patients with positive cultures was 11.11±5.24 years, and50.82% were female. The mean CRP level in the study groupwas 48.48±59.76, with higher levels observed in Gram-negativeinfections (p<0.001). The most frequently isolated organismwas Staphylococcus epidermidis (41.04%), followed byStaphylococcus aureus (4.48%). Gram-positive bacteria accountedfor 87.91% of isolates, fungi for 1.09%, and Gram-negative bacteria(GNB) for 11.00%. Among GNBs, Enterobacter accounted for3.67%, Salmonella for 2.17%, and Klebsiella for 0.54%. Methicillinresistance was detected in 18.8% of S. aureus isolates and in 85.0%of S. epidermidis isolates. No third-generation cephalosporin(TGC) resistance was found in Salmonella isolates. For Klebsiella,TGC resistance was 100%, while carbapenem resistance was7.1%. In Acinetobacter species, amikacin resistance was 46.7%,meropenem resistance was 37.5%, and TGC resistance was 16.7%.Conclusion: Gram-positive bacteremia was common, with a highrate of methicillin resistance. While third-generation cephalosporincould be excluded as treatment options for Klebsiella, sensitivityto these antibiotics persists in Salmonella infections. Empiricalantibiotic selection for bacteremia may vary depending on clinicalsettings.