Prognostic Factors and Therapeutic Optimization in Hematologic Patients with Candida tropicalis Bloodstream Infections: A Single-Center Retrospective Study

Background : Candida tropicalis bloodstream infection (CTBI) has emerged as a leading cause of invasive candidiasis in immunocompromised hosts, yet data on prognostic indicators and optimal treatment strategies in hematologic malignancy patients are limited. We conducted a single-center, retrospective cohort study to identify key risk factors for 30-day mortality and to evaluate the effect of susceptibility-guided and combination antifungal regimens on survival. Materials and Methods : In this single-center retrospective cohort (Jan 2020–Dec 2024), we reviewed 87 adult hematologic malignancy patients (≥18 years) with at least one C. tropicalis –positive blood culture. Demographics, infection characteristics, laboratory tests, hematologic disease status, antifungal regimens, and susceptibility‑guided adjustments were analyzed. Results: The 30-day mortality was 33.3% (29/87). Non-Hodgkin lymphoma (27.6% vs. 5.2%, P =0.028), relapsed/refractory disease (82.8% vs. 25.9%, P <0.001), and prior chimeric antigen receptor T-cell therapy (CAR-T, 24.1% vs. 5.2%, P =0.014) were significantly associated with death. Elevated D-dimer >3685 μg/L (41.4% vs. 6.9%, P <0.001), hypoalbuminemia (44.8% vs. 19.0%, P =0.011), hypoglobulinemia (57.1% vs. 15.5%, P =0.008), and serum creatinine >111 μmol/L (17.2% vs. 0.0%, P =0.003) were markedly higher in non-survivors. Azole resistance was 70%–75%, whereas amphotericin B and flucytosine remained 98.9%–100% susceptible. Susceptibility-guided regimen adjustment (70.1%) correlated with lower mortality (58.6% vs. 75.9%, P =0.005). Multivariable Cox regression analysis identified D-dimer >3685 μg/L (adjusted HR 4.97; 95% CI: 1.93 – 12.84; P =0.001), susceptibility concordance (adjusted HR 0.04; 95% CI: 0.01 – 0.14; P <0.001), and relapsed/refractory disease (adjusted HR 9.36; 95% CI: 2.54 – 34.53; P =0.001) as independent predictors. Combination therapy with amphotericin B and echinocandin was associated with a median survival of 39.0 days, significantly longer than the 12.0-day median survival observed with azole monotherapy (log-rank test: χ² = 8.102, P = 0.044). Conclusion: In hematologic malignancy patients, elevated D-dimer and relapsed/refractory status predict higher mortality, whereas susceptibility-guided adjustment markedly improves survival. Given high azole resistance, rapid species-specific testing and amphotericin B–echinocandin combinations warrant priority. Prospective multicenter trials are needed to refine treatment algorithms.