Abstract Topic: 30. Infections in hematology (incl. supportive care/therapy)
Background: Bacillus cereus (B. cereus) is a gram-positive rod widely distributed in nature and is generally known as a causative microorganism of food poisoning. Although rare, it can cause bloodstream infection through intravascular catheters and central nervous system (CNS) infection due to disseminated lesions, especially in immunosuppressed patients. However, few studies have had a large sample size of B. cereus bacteremia in patients with hematologic malignancies, and the risk factors, management, and prognosis.
Aims: We investigate the risk factors, management, and prognosis of B. cereus bacteremia in patients with hematologic malignancies.
Methods: Patients diagnosed with B. cereus bacteremia with hematologic malignancy were selected from cases at our hospital from April 2004 to May 2022. Also, we searched the electronic databases PubMed, Embase, and Ichushi on May 2022. Univariate analysis (χ2 test or Fisher’s exact probability ratio test) was performed with death as the outcome. Multivariate analysis (logistic regression analysis) was then performed on the factors that showed significant differences in univariate analysis. A p-value less than 0.05 was considered statistically different.
Results: A total of 176 patients (8, 86, 3, and 79 cases were selected from our hospital, PubMed, Embase, and Ichushi, respectively), with a median age of 41 ± 26 years and 99 (56%) males. Acute leukemia accounted for 141 (80%) of the patients. Death occurred in 93 patients (53%). In univariate analysis, neutropenia, CNS infection, gastrointestinal infection, respiratory infection, glycopeptide antimicrobial use, and management with source control were significantly associated with death. Multivariate analysis showed that the odds ratios for death were significantly different in patients with CNS infection (OR; 3.49, 95% CI; 1.25-9.80), gastrointestinal infection (OR; 5.22, 95% CI; 1.82-15.0), respiratory infection (OR; 8.98, 95% CI; 1.62-49.9), glycopeptide antimicrobial use (OR; 0.10, 95% CI; 0.03-0.31), and management with source control (OR; 0.11, 95% CI; 0.03-0.37).
Summary/Conclusion: Patients with acute leukemia are at high risk for B. cereus bacteremia and a high mortality rate. CNS, gastrointestinal and respiratory infections were independent risk factors for mortality, and management with source control and glycopeptide antimicrobial use were independent protective factors.
Keywords: Febrile neutropenia, Acute leukemia, Infection