[Clinical characteristics and prognostic analysis of carbapenem-resistant Enterobacteriaceae bloodstream infections in patients with hematologic diseases].

Objectives: This study aimed to analyze the clinical and molecular characteristics of carbapenem-resistant Enterobacteriaceae (CRE) bloodstream infection (BSI) in patients with hematological diseases and to explore prognostic risk factors. Methods: This retrospective study included patients with hematologic diseases with CRE BSI at the Institute of Hematology and Blood Diseases Hospital from January 2015 to December 2022. The clinical features, carbapenemase test results, antimicrobial treatments, and outcomes were analyzed. Results: A total of 120 patients developed CRE BSI. Escherichia coli (58/120, 48.3%) was the most prevalent Enterobacteriaceae, followed by Klebsiella pneumoniae (52/120, 43.3%). A total of 93 CRE strains were tested for carbapenemase, of which 75 strains produced carbapenemase (metalloenzyme: 51 strains; serine enzyme: 24 strains). The 30-day mortality rate after BSI was 24.2% (29/120). Univariate analysis revealed significantly lower mortality in patients treated with the ceftazidime-avibactam-containing regimen than in those treated with other antibiotics (7.8% vs 36.2%, P<0.001). Moreover, initiating active therapy within 24 h of BSI onset significantly reduced mortality (15.0% vs 33.3%, P=0.019). The proportion of patients with CRE colonization receiving active therapy within 12 and 24 h was significantly higher compared with patients without colonization (12 h: 14.5% vs 34.1%, P=0.012; 24 h: 40.8% vs 65.9%, P=0.008). Multivariate analysis revealed that septic shock (HR=24.436, 95% CI 4.148 - 143.966, P<0.001) and pulmonary infection (HR=9.346, 95% CI 2.718-32.140, P<0.001) were independent risk factors for death within 30 days. Appropriate therapy was initiated within 24 h (HR=0.225, 95% CI 0.059 - 0.851, P=0.028), and treatment with the ceftazidime-avibactam-containing regimen (HR=0.082, 95% CI 0.018-0.362, P=0.001) significantly reduced mortality. Conclusion: The prognosis of CRE BSI in patients with hematological diseases is poor. Timely, appropriate therapy and receipt of a ceftazidime-avibactam-containing regimen can improve survival and prognosis.