Antimicrobial Lock Therapy: Is it a Real Savior in Pediatric Hematopoetic Stem Cell Transplant (HSCT) Patients?

Objective: Central line-associated bloodstream infection (CLABSI) is a significant cause of morbidity and mortality in patients undergoing hematopoietic stem cell transplantation (HSCT). Antimicrobial lock treatment (ALT), when utilized alongside systemic antibiotics, may be lifesaving when catheter removal (CR) is not feasible.

Materials and Methods: This retrospective study analyzed the clinical, laboratory, and microbiologic characteristics of CLABSI episodes of pediatric patients who underwent HSCT and applied ALT.

Results: There were 137 cases of CLABSI (63.5 male) who were given ALT. The median age was 48 (3-204) months. The most common causative microorganism was Gram-negative bacteria, encountered in 85 patients (62%). Forty-six patients (33.6%) had Gram-positive bacterial growth, whereas 6 had (4.4%) fungal infection. ALT was successful in 77.4% of the patients (n=106). CR was required in 25 patients (18.2%). The CLABSI-related mortality rate was 12.4%. When the outcome of ALT was evaluated, post-transplantation cyclophosphamide (PTCy) use, fungal growth, persistent bacteremia/fungemia, re-HSCT, inappropriate empirical antibiotic use, hypotension, and pediatric intensive care unit admission were significantly more common in the “unsuccessful” ALT group. The patients in the unsuccessful group had higher C-reactive protein [110.2 (1.10-323.5) mg/L] levels when compared to the successful ALT group [58 (0.2-450.3) mg/L] (p=0.029). The presence of hypotension, HLA-mismatch transplantation, and persistent bacteremia/fungemia were independent risk factors for ALT failure.

Conclusion: ALT can be an effective catheter-saving strategy in HSCT pediatric patients. Nevertheless, patients should be monitored very closely during ALT, and the presence of certain risk factors should be taken into account.