Management of Recurrent Vancomycin-resistant Bacteremia With Oritavancin: A Case Report.

Background/aim: Vancomycin-resistant Enterococcus causes significant morbidity, mortality, and excess healthcare costs when compared to vancomycin-susceptible isolates. Patients with hematological malignancies, especially those who undergo hematopoietic stem cell transplantation, are at a particularly high risk for infections with vancomycin-resistant Enterococcus, with mortality ranging from 40-100%. Linezolid and daptomycin are the two most commonly used antibiotics for treatment of vancomycin-resistant enterococcal infections, however, there has been recent emergence of resistance to these drugs as well.

Case Report: We report the case of a 48-year-old male with hematological malignancy and graft failure post hematopoietic stem cell transplantation complicated by dialysis-dependent acute kidney injury and recurrent neutropenic fevers due to vancomycin-resistant Enterococcus faecium (VREf) bacteremia. Despite central line changes, and strict aseptic precautions, the bacteremia returned, showing resistance to daptomycin and linezolid after the second recurrence. As a final effort, using limited clinical data and in vitro studies, we utilized oritavancin off-label as salvage therapy for refractory VREf bacteremia, with subsequent clearance of blood cultures.

Conclusion: This is a rare case of successful off-label use of oritavancin for recurrent multidrug-resistant VREf bacteremia in a patient with hematological malignancy after undergoing hematopoietic stem cell transplantation. It is important to increase awareness of the potential use of this novel antibiotic with increasing resistance of VREf to first-line agents.