Epidemiology and outcomes of Candida spp. bloodstream infections in cancer patients: a comparative retrospective study from a German tertiary cancer center.

Background: Bloodstream infections (BSI) due to Candida spp. significantly contribute to morbidity and mortality among cancer patients. Understanding their clinical course, risk factors, and outcomes compared to bacterial BSI is essential.

Aim: We aim to elucidate the epidemiology and risk factors associated with Candida BSI compared to bacterial BSI in cancer patients.

Methods: We analyzed epidemiological data of Candida BSI versus bacterial BSI among cancer patients, primarily with hematological malignancies. Blood cultures were obtained upon clinical suspicion, with species identification by VITEK 2 and MALDI-TOF. Susceptibility testing utilized VITEK 2 or antibiotic gradient tests.

Results: Candida BSI was associated with higher 30-day mortality compared to bacterial BSI (Hazard ratio (HR) 4.5, 95% CI 2.5-8.1, p < 0.001) occurring predominantly in patients with relapsed/refractory disease. Univariate analysis identified risk factors for Candida BSI: hypoalbuminemia (Odds ratio (OR) 9.13, 95% CI 2.7-57, p = 0.003), prior ICU/MC stay (OR 3.91, 95% CI 1.38-9.65, p = 0.005), palliative treatment (OR 3.42, 95% CI 1.52-7.4, p = 0.002), parenteral nutrition (OR 2.44, 95% CI 0.9-5.5, p = 0.039) and prior allogeneic HSCT (OR 2.28, 95% CI 0.92-5.13, p = 0.056). Risk factors identified by multivariate analysis were palliative therapy (OR 5.23, 95% CI 3.14-8.71, p = 0.001), hypoalbuminemia (OR 9.02, 95% CI 4.23-19.2, p = 0.004), and prior ICU/IMC stay (OR 4, 95% CI 2.31-6.92, p = 0.011). In patients with confirmed Candida BSI, delayed initiation of antifungal was associated with worse outcomes.

Conclusion: Compared to bacterial BSI events, Candida BSI are associated with significantly higher 30-day mortality, primarily affecting heavily pretreated patients with relapsed or refractory disease.