Antimicrobial therapy of sepsis caused by carbapenem-resistant Klebsiella pneumoniae in patients with hematological malignancies

Abstract

Objective. To compare the efficacy of ceftazidime-avibactam and aztreonam combination therapy with “standard” therapy in patients with hematological malignancies and sepsis, caused by carbapenemresistant K. pneumoniae. Materials and Methods. In this open, single center prospective-retrospective, cohort study, during 2019–2022, we analyze medical documentation of 81 hospitalized patients with hematologic malignancies and K. pneumoniae sepsis. K. pneumoniae was identified by MALDI-TOF mass-spectrometry; antimicrobial susceptibility testing was performed in accordance with current versions of EUCAST guidelines. Patients with sepsis, caused by carbapenem-resistant K. pneumoniae isolates (n = 53), received either ceftazidimeavibactam plus aztreonam combined therapy (1st group, n = 26), or “standard” antimicrobial therapy (2nd group, n = 27). Results. K. pneumoniae sepsis was diagnosed in 81 patient with hematologic malignancies during 3 years study period. In 53 (65.4%) cases sepsis was caused by carbapenem-resistant K. pneumoniae isolates. Mortality in patients that received combination therapy with ceftazidime-avibactam and aztreonam was significantly lower (34.6%), than in patients that received other antimicrobial therapy (63.0%), p = 0.039. When ceftazidime-avibactam plus aztreonam therapy was started ≥7 days after the onset of infection the mortality rates in both groups were similar (p > 0.05). Conclusions. The incidence of carbapenem-resistance in K. pneumoniae sepsis in hematologic malignancies was 65.4% in the present study. Early administration of ceftazidime-avibactam and aztreonam combined therapy was associated with lower mortality (34.6%) comparing alternative antibiotic regimens (63.0%).