Risk Factors for Mortality and Outcomes in Hematological Malignancy Patients with Carbapenem-Resistant Klebsiella pneumoniae Bloodstream Infections

BACKGROUND: This study aimed to identify risk factors for mortality and outcomes in hematological malignancy (HM) patients with bloodstream infection (BSI) caused by carbapenem-resistant Klebsiella pneumoniae (CRKP). METHODS: A retrospective study was conducted at a tertiary teaching hospital in Henan Province, China, between January 2018 and December 2021. All BSIs caused by CRKP in hospitalized HM patients were identified. Data on patient demographics, disease, laboratory tests, treatment regimens, outcomes of infection, and the antimicrobial susceptibility of each isolate were collected from medical records. RESULTS: A total of 129 patients with CRKP BSI were included in the study, and the 28-day mortality rate was 80.6% (104/129). In Cox analysis an absolute neutrophil count < 500 at discharge (hazard ratio [HR] 6.386, 95% confidence interval [CI] 3.074–13.266, p < 0.001), intensive care unit admission (HR 1.834, 95% CI 1.065–3.157, p = 0.029), and higher Pitt bacteremia score (HR 1.185, 95% CI 1.118–1.255, p < 0.001) were independent risk factors associated with 28-day mortality. Survival curve analysis indicated that compared with ceftazidime-avibactam-based therapy, both polymyxin b (HR 8.175, 95% CI 1.099–60.804, p = 0.040) and tigecycline (HR 14.527, 95% CI 2.000–105.541, p =0.008) were associated with a higher risk of mortality. CONCLUSION: In HM patients CRKP BSI resulted in high mortality. Intensive care unit admission, higher Pitt bacteremia score, and absolute neutrophil count < 500 at discharge were independently associated with higher mortality. Early initiation of new agents such as ceftazidime-avibactam may improve outcomes.