小児がん患者における細菌分離株の抗菌薬感受性プロファイル：前向き横断研究

Paediatric cancer patients are highly susceptible to bloodstream infections (BSIs), which are a leading cause of morbidity and mortality in this population. However, data focusing on BSI pathogens and resistance profiles in paediatric oncology patients in Ghana are lacking. This study aimed to characterize the spectrum of bacterial pathogens and their antibiotic susceptibility patterns among paediatric cancer patients with BSIs at the national tertiary referral centre, to inform empiric therapy and infection control strategies.

A prospective cross-sectional study was conducted at Korle Bu Teaching hospital from April to September 2023. Paediatric cancer patients (ages 1-18) presenting with fever on admission were consecutively sampled and enrolled, excluding those on antibiotics for BSI. Blood cultures were performed using standard microbiological techniques, and isolates were identified by conventional biochemical tests. Antimicrobial susceptibility testing was done using the modified Kirby-Bauer disk diffusion method on Mueller-Hinton agar, interpreted according to Clinical and Laboratory Standards Institute (CLSI) 2021 guidelines. Patient demographics and clinical data were collected, and infection prevalence was calculated. Associations were analysed by chi-square tests, with significance at p < 0.05.

BSIs were confirmed in 22% of patients (22/100). Gram-positive organisms predominated (59.1% of isolates), chiefly Staphylococcus aureus (31.8%), coagulase-negative staphylococci (22.7%) and Streptococcus pneumoniae (4.5%). Gram-negatives (40.9%) included Klebsiella pneumoniae (18.2%), Pseudomonas aeruginosa (13.6%), and Escherichia coli (9.1%). No significant difference in BSI occurrence was observed by gender (p > 0.5). All Gram-negative isolates were susceptible to meropenem and amikacin, whereas over half of all isolates were resistant to gentamicin. For Gram-positives, cefoxitin susceptibility was 85.7% and S. aureus showed high resistance to penicillin (71.4% resistant) and gentamicin (85.7% resistant). Overall, 18.2% of isolates were multi-drug resistant (MDR) bacteria which were more common in Gram-negatives (75%) than Gram-positives (25%).

BSIs constitute a significant complication in paediatric cancer patients in this Ghanaian centre. Meropenem and amikacin were highly effective against Gram-negative bacteria, whereas substantial resistance was observed to gentamicin and ceftriaxone. There is the need to revise the empiric fever protocol at the centre to consider amikacin instead of gentamicin, The emergence of MDR organisms underscores the need for robust antibiotic stewardship and infection control measures at the oncology clinic.