Bloodstream infections associated with Serratia Marcescens in children

Serratia marcescens is an important pathogen increasingly associated with nosocomial infections, particularly in neonates and immunocompromised children. This study aimed to evaluate the clinical features, antimicrobial resistance, and mortality risk factors of pediatric patients with S. marcescens bacteremia. A retrospective analysis was conducted on 77 pediatric patients (0-18 years) diagnosed with S. marcescens bacteremia between January 2017 and December 2021. Demographics, underlying conditions, antimicrobial susceptibility, treatments, and mortality-related factors were assessed. The median age was 3 months (1-15.5 months), and 32.5% were female. Overall mortality was 31.2%. Prematurity was observed in 58.5% of cases. Chronic diseases were significantly more common among deceased patients (p = 0.025). The most frequent comorbidities were neurometabolic disorders (37.7%), surgical conditions (29.3%), and chronic lung diseases (12.1%). Empirical therapy included meropenem in 57.1% and amikacin in 29.9% of patients. Antibiotic regimens were modified in 65.7% due to resistance. Resistance rates were 50% for meropenem, 38.9% for piperacillin-tazobactam, 2.5% for amikacin, and 9% for tigecycline. A substantial proportion of isolates exhibited multidrug resistance. Serratia marcescens bacteremia in children is associated with high mortality and alarming antimicrobial resistance, especially in intensive care settings. Careful empirical therapy selection, early recognition, and risk factor management are essential to improve clinical outcomes.