Cefiderocol in the Successful Treatment of Complicated Hospital-Acquired K. pneumoniae NDM, OXA48 Intraabdominal Infection.

Background: Case Presentation: A 72-year-old female patient with sepsis caused by KP NDM, OXA 48 was admitted to the Intensive Care Unit, immediately after an emergency graftectomy (of a recently transplanted kidney) complicated with bleeding. Because of suspicion of intra-abdominal infection, a broad-spectrum empirical antibiotic therapy was initiated (meropenem, vancomycin, colistin). The patient underwent an abdominal revision 48 hours after admission. On the 3rd day of hospitalization, diagnosis of a septic shock with etiology of KP NDM, OXA 48 was made. The strain had sensitivity to a colistin and a cefiderocol. On 13th day in the ICU a relaparotomy was performed. Again, KP strains with sensitivity to cefiderocol only, were cultured from intra-abdominal fluid. Aztreonam, in combination with meropenem/vaborbactam, were included in the treatment and were used together with colistin and tigecycline. In the following days, the inflammatory markers decreased slightly, but the patient's general condition did not improve. On day 27 ceftazidime/avibactam and aztreonam were added, while colistin, meropenem/vaborbactam and fosfomycin were discontinued. On 37th day of hospitalization, cefiderocol became available in hospital and was included in the treatment. Cefiderocol monotherapy was continued for 8 days. After 4 days of cefiderocol treatment, the inflammatory markers CRP and PCT decreased and a significant improvement in patient's condition were observed. On day 56, the patient was transferred to another department. Conclusion: A surgical debridement of a source infection, and usage of meropenem/vaborbactam or ceftazidime/avibactam together with aztreonam and colistin allowed survival of the patient but not full recovery. Ultimately, only the cefiderocol monotherapy was effective in treatment of the patient with septic shock of KP NDM OXA 48 etiology.