A Case of Fatal Cupriavidus gilardii Sepsis Following Cord Blood Transplantation: Pitfalls of Novel Antimicrobial Agents

The duration of neutropenia is prolonged in cord blood transplantation, rendering infection management critical. Carbapenems have traditionally been employed as last-resort antibiotics; however, carbapenem-resistant bacteria have emerged as major concerns worldwide. Cefiderocol (CFDC) is a novel antimicrobial agent that exhibits activity against carbapenem-resistant non-fermenting gram-negative bacilli, such as resistant Pseudomonas aeruginosa and Stenotrophomonas maltophilia, and has thus attracted considerable attention. Herein, we report a case in which a patient who was undergoing cord blood transplantation developed gram-negative rod sepsis after meropenem administration. CFDC was administered before the microbiological results were obtained, but the patient died of septic shock. The causative organism was later identified as Cupriavidus gilardii, which was resistant to novel antimicrobial agents, including CFDC, ceftazidime/avibactam, and ceftolozane/tazobactam. However, it was susceptible to cefepime and cefotaxime, suggesting a potential pitfall in the sole reliance on novel antibacterial drugs. The incidence of Cupriavidus gilardii infection is rare, with only seven cases reported to date. This is the first reported case in the context of hematopoietic cell transplantation and the second diagnosed case using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Moreover, this report presents a discussion based on a review of the relevant literature.