Antibiotic Resistance and Risk Factors for Mortality of Blood Stream Infections (BSIs) with Escherichia coli in Patients with Hematological Malignancies

Objective To analyze the risk factors for mortality of blood stream infections （BSIs） caused by Escherichia coli in the patients with hematological malignancies. Methods There were 110 Escherichia coli BSIs patients with hematological malignancies included in recent five years. Among them, 77 cases had BSIs caused by extended-spectrum-beta-lactamase (ESBL)-producing Escherichia coli (ESBL-EC group), while 33 cases had BSIs with non-ESBL-producing Escherichia coli (non-ESBL-EC group). The antibiotic resistance and clinical features were compared between the two groups, and the risk factors for death within 30 d were analyzed. Results Less than 10% of the isolates were resistant to carbapenems and amikacin. Between ESBL-EC group and non-ESBL-EC group, the clinical symptoms, prior use of antibiotics or antifungal agents, risk factors for infection, 30 d mortality rates were not significantly different (P＞0.05). A logistic regression analysis confirmed that non remission of hematologic malignancies (odds ratio=9.575, 95% confidence interval 1.546-59.312, P=0.015) and inappropriate initial antibiotic therapy (odds ratio=8.806, 95% confidence interval 1.527-50.772,P=0.015) were independent risk factors for 30 d mortality. Conclusion The use of effective antimicrobial treatment as early as possible could reduce the risk of death for hematological malignancies patients suffering Escherichia coli BSIs.