Cefiderocol as a Successful Therapy for Osteomyelitis Due to XDR Pseudomonas aeruginosa: A Case Report and Literature Review

<b>Background</b>: Carbapenem-resistant <i>Enterobacterales</i> and difficult-to-treat resistance (DTR) <i>Pseudomonas aeruginosa</i> are a growing public health issue. Cefiderocol demonstrated activity against β-lactamase-producing Gram-negative bacteria (GNB). However, bone PharmacoKinetics (PK) data is lacking. Here, we report a case of post-traumatic chronic osteomyelitis caused by extensively drug-resistant (XDR) <i>Pseudomonas aeruginosa</i> which was successfully treated with cefiderocol. Moreover, we conducted a non-systematic review of the available literature. <b>Case Report</b>: We described the case of a 64-year-old man who was admitted to a traumatology ward after a work accident caused crushing of his left foot. Microbiological tests on intraoperative biopsies demonstrated XDR <i>P. aeruginosa</i> and <i>K. oxytoca</i>. Despite the administrations of different antibiotics regimens and multiple surgical revisions, the patient developed chronic osteomyelitis. To prevent amputation, cefiderocol was prescribed for six weeks, resulting in a complete clinical resolution of osteomyelitis. <b>Review of the Literature</b>: We performed a non-systematic review of the literature searching the public databases PubMed and Google Scholar. We identified nine case reports. In most patients (60%) the cause of osteomyelitis was post-surgical, and all the reported cases were healthcare associated. Osteomyelitis treatment required both antimicrobial therapy and surgery in all the cases described. Cefiderocol was often prescribed in association with other antibiotics (70%). Clinical cure was described in all the reported cases. <b>Conclusions</b>: This study highlights that cefiderocol is safe and efficacious to treat osteomyelitis caused by carbapenem-resistant GNB. However, evidence is limited to a few case reports.