Therapeutic efficacy of different sulperazon dosing regimens in carbapenem-resistant Klebsiella pneumoniae: a retrospective analysis of 209 cases.

Objectives: Carbapenem-resistant Klebsiella pneumoniae (CRKP) infections pose significant clinical challenges worldwide due to limited therapeutic options and high mortality. Sulperazon (cefoperazone/sulbactam) has demonstrated activity against multidrug-resistant (MDR) organisms; however, the optimal dosing regimen for CRKP remains unclear. This study aimed to evaluate the clinical efficacy, microbiological outcomes, and safety of different sulperazon dosing in CRKP infections.

Methods: A retrospective analysis was conducted on 209 adult patients with CRKP infections treated with sulperazon for at least 48 hours at Bengbu First People's Hospital between January 2020 and December 2022. Patients were grouped into a standard-dose group (≤3 g/day, n=112) and a high-dose group (>3 g/day, n=97). Clinical cure, microbiological eradication, treatment failure, 28-day mortality, and incidence of adverse events were compared between groups.

Results: The cohort was predominantly elderly (mean age 67.3 ± 15.2 years) and male (65.1%). The most frequent carbapenemase genes were bla_KPC-2 (65.6%) and bla_NDM-1 (23.0%). Virulence factors, including adhesins (72.2%), iron-acquisition systems (63.2%), capsule synthesis genes (58.9%), and the hypermucoviscosity regulator rmpA (42.6%) were frequently detected. Compared with the standard-dose group, the high-dose group showed significantly increased clinical cure rates (64.9% vs. 43.8%; P=0.002) and microbiological eradication rates (69.1% vs. 46.4%; P=0.001), along with lower rates of treatment failure (10.3% vs. 24.1%; P=0.011) and 28-day mortality (8.2% vs. 20.5%; P=0.015), without an increase in adverse events.

Conclusion: High-dose sulperazon demonstrated superior clinical efficacy and equivalent safety to standard dosing in the treatment of CRKP infections, supporting dose optimization to improve patient outcomes.