2044P - Bloodstream infections (BSI) in cancer patients: Epidemiology, antibiotic therapy and risk factors related to mortality

Background

BSI are a frequent and severe complication in cancer. Recent changes in oncological treatment, supportive care and development of new antimicrobial therapies could have affected its epidemiology, management and outcomes. Our aim is to describe clinical and microbiological features, antibiotic therapy, outcomes and mortality-related risk factors of BSI in cancer patients.

Methods

We performed a retrospective, observational, unicentric study. Microbiologically-confirmed BSI episodes in cancer patients between January 2017 and December 2021 were collected. We analysed clinical and microbiological data, empirical antibiotic treatment (EAT) and outcomes. A binary logistic regression model was used to detect variables related to 7 and 30-days mortality. P values <0.05 were considered significant.

Results

438 episodes of BSI were documented in 362 patients. Most frequent neoplasms were pancreatobiliary (25.1%), colorectal (16.9%), lung (11.9%) and breast (9.1%) tumours. 78.1% were metastatic. 72.1% had received chemotherapy in the previous month. The most common sources of BSI were vascular catheters (26.9%), cholangitis (23.1%) and other abdominal infections (22.8%). Gram-negative bacteria (GNB) were isolated in 60.3% of cases and Gram-positive bacteria in 45.4%. Yeasts were isolated in 3.9% of cases. Most common organisms were E. coli (29.7%), Klebsiella spp. (15.1%), coagulase-negative staphylococcus (12.6%) and S. aureus (10.3%). Most used EAT was piperacillin/tazobactam (43.2%), followed by meropenem (18.3%), amoxicilin/clavulanic acid (16%) and vancomycin (14.8%). Adequate EAT was given to 76.3% of patients. Mortality at 7 and 30 days was 11.2% and 24.4%, respectively. Statistical analysis showed lung cancer, respiratory source, yeasts and Pseudomonas spp. as independent risk factors for 7 and 20-days mortality.

Conclusions

BSI is a severe complication associated to elevated mortality in cancer patients. Most frequent sources of BSI are vascular catheters, cholangitis and abdominal infections. Most of them occur in patients with metastatic digestive tumours and are caused by GNB. Lung cancer, respiratory infections, isolation of yeasts and Pseudomonas spp. could imply a worse prognosis.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.