Clinical and Microbiologic Outcomes of Tigecycline in Pediatric Patients With Multidrug-resistant Gram-negative...

Increasing prevalence of multidrug-resistant Gram-negative bacteria (MDR-GNB) necessitates the use of tigecycline in children, yet pediatric-specific data are limited.

To evaluate the clinical and microbiologic outcomes, susceptibility patterns and safety profile of tigecycline in pediatric MDR-GNB infections.

A retrospective observational study was conducted at a tertiary university hospital from January 2015 to December 2024. We included patients aged ≤18 years who received tigecycline for ≥48 hours for confirmed MDR-GNB infections.

Forty-six treatment episodes were identified in 43 patients (median age: 16 months; interquartile range, 2-100). The majority (91.3%) required intensive care, with ventilator-associated pneumonia (56.5%) being the primary indication. Causative pathogens were carbapenem-resistant Acinetobacter baumannii (69.6%), carbapenem-resistant Enterobacterales (23.9%) and Stenotrophomonas maltophilia (6.5%). Clinical improvement was achieved in 73.9% of episodes, and microbiologic eradication in 60.9%. Although 45.7% of isolates were nonsusceptible to tigecycline (minimum inhibitory concentration >2 mg/L), clinical success remained high. Higher improvement rates were observed in children aged ≥8 years and those receiving a loading dose, though statistical significance was not reached. Adverse events were mild and predominantly gastrointestinal; no treatment discontinuations due to toxicity were reported.

Tigecycline is a viable salvage therapy for severe pediatric MDR-GNB infections, demonstrating a manageable safety profile. However, the mortality rate of 23.9% and relatively modest microbiologic eradication rates underscore the complexity of such infections and emphasize the pressing need for pharmacokinetic data to refine dosing in younger children, where evidence remains sparse.