Bacterial profile and antimicrobial susceptibility patterns of blood culture isolates in pediatric patients at children hospital, Sukkur: a one-year retrospective analysis

Abstract

Background and Objectives: Bloodstream infections (BSIs) are an important cause of morbidity and mortality among ne- onates and children. Increasing antimicrobial resistance (AMR), particularly among Gram-negative organisms, complicates empirical antimicrobial therapy. Local antimicrobial susceptibility data are essential for guiding empirical treatment and antimicrobial stewardship.

Materials and Methods: A retrospective descriptive study was conducted at Children Hospital, Sukkur, Pakistan, from July 2024 to June 2025. Blood culture data from pediatric patients from birth to 14 years of age were reviewed. Only the first positive blood culture from each patient during the study period was included in the primary analysis, while subsequent positive cultures from the same patient were excluded. Organism distribution and antimicrobial susceptibility patterns were analyzed. Antimicrobial susceptibility testing (AST) had been performed in the hospital microbiology laboratory according to applicable Clinical and Laboratory Standards Institute (CLSI) recommendations. Because the retrospective records did not contain sufficient information to reliably confirm the exact AST technique used, the specific susceptibility-testing methodol- ogy could not be retrospectively established.

Results: A total of 11,962 blood cultures were processed during the study period, of which 4,151 (34.7%) were positive. Gram-positive bacteria accounted for 2,276 (54.8%) isolates and Gram-negative bacteria for 1,856 (44.7%). Nineteen (0.5%) positive cultures yielded fungal organisms and were excluded from the bacterial analysis. Coagulase-negative staphylococci (CoNS) were the most frequently isolated bacterial organisms, accounting for 2,125 isolates (51.2% of all positive cultures), followed by Klebsiella spp. (526, 12.7%), Serratia spp. (490, 11.8%), and Acinetobacter spp. (259, 6.2%). Gram-negative organisms demonstrated marked resistance to several commonly used antimicrobial agents. Salmonella Typhi demonstrated high susceptibility to azithromycin (93.6%) and meropenem (97.6%), whereas susceptibility to ceftriaxone (43.6%), cefix- ime (9%), ciprofloxacin (0%), and trimethoprim-sulfamethoxazole (15.7%) was low. Vancomycin and linezolid demonstrated 100% susceptibility among the tested CoNS, Staphylococcus aureus, and Enterococcus spp. isolates.

Conclusion: This one-year analysis demonstrates a substantial burden of antimicrobial resistance among pediatric blood- stream isolates at Children Hospital, Sukkur. CoNS were the most frequently isolated organisms; however, this finding should be interpreted cautiously because the clinical and microbiological information required to distinguish true CoNS bacteremia from blood culture contamination was not consistently available. Regular institution-specific antibiogram surveil- lance, antimicrobial stewardship, and strengthened infection prevention and control measures are warranted.