Cefiderocol for the Treatment of Nosocomial Bloodstream Infections Caused by Stenotrophomonas maltophilia: A Case Series and Literature Review

Introduction: The treatment of Stenotrophomonas maltophilia bloodstream infections (BSI) remains challenging due to the organism's intrinsic multidrug resistance and the potential side effects of commonly used first-line antibiotics. Methods: Here, we describe four cases of S. maltophilia BSI treated with cefiderocol (≥ 72 h) in different Italian hospitals. Additionally, we conducted a PubMed search to identify other studies reporting cases of S. maltophilia BSI managed with cefiderocol. Results: We reviewed a total of 8 cases of S. maltophilia BSI [median age 52.5 years (Q1–Q3 27.5–61.0), 50% males] treated with cefiderocol, including ours. BSI sources were mainly central venous catheters (62.5%) and the lower respiratory tract (25.0%). Cefiderocol was used as first-line therapy in 87.5% of patients (7/8), with a median treatment duration of 14 days (IQR 6.2–16.0). Combination therapy was administered in 62.5% of cases. Infection source control was required in 75.0% and achieved in 40.0%. Clinical success was observed in 62.5% of patients, with microbiological eradication in 87.5%. In-hospital mortality occurred in 37.5% of cases, with one death directly attributable to S. maltophilia. No significant differences were observed in terms of outcomes between cefiderocol monotherapy and combination therapy. Conclusions: Based on our findings and a review of the literature, cefiderocol-based regimens show promise as an effective treatment option for S. maltophilia BSI, warranting further investigation in larger studies.