Usefulness of daptomycin lock therapy in children with catheter-related bacteremia after failed vancomycin lock therapy

PURPOSE: Catheter-related bacteremia (CRB) is a significant cause of morbidity, resource expenditure and prolonged hospital stays in patients with long-term catheters, whose numbers have increased considerably in recent years. Antibiotic lock therapy reaches high concentrations in the catheter, allowing good penetration into the biofilm, being vancomycin the most commonly used one in gram-positive infections. Several authors have recently reported the superior in vitro efficacy of daptomycin compared with vancomycin, especially for eradicating biofilms. Although there is some data on the use of daptomycin for antibiotic lock in animal models and adults, there are no data on its use in children. METHODS: A descriptive study was conducted in a tertiary hospital, including patients younger than 16 years in whom daptomycin lock therapy was employed between 2018 and 2022. RESULTS: We report three pediatric patients in whom CRB was confirmed on admission by paired blood cultures positive for CoNS sensitive to vancomycin, daptomycin and linezolid. All patients started vancomycin lock therapy and systemic antibiotic therapy with proven sensitivity for the isolated bacteria, without achieving negative blood cultures. Due to the persistence of positive cultures, vancomycin lock therapy was replaced by daptomycin, and blood cultures turned negative, with no relapses or need for catheter removal. CONCLUSION: The use of daptomycin lock therapy could be considered in children with CoNS catheter infection, especially when other antibiotic lock therapy had failed.