Epidemiology and Characteristics of Invasive Yeast Infections in Patients with Hematologic Diseases: 12-Year Single-Center Retrospective Cohort Study

Invasive yeast infections (IYIs) remain a significant cause of morbidity and mortality in patients with hematologic diseases. We retrospectively analyzed 193 IYI episodes among 179 patients admitted to a tertiary hematology hospital (2012-2023). <i>Candida</i> species accounted for 91.7% (n = 177), while non-<i>Candida</i> yeasts comprised 8.3% (n = 16). Among invasive candidiasis, non-<i>albicans Candida</i> spp. were predominant, representing 76.8% (136/177), with <i>C. tropicalis</i> (36.2%, 64/177) being the most frequently isolated species. Among non-<i>Candida</i> yeasts, <i>Cryptococcus neoformans</i> (n = 10) was the most commonly identified pathogen. The incidence and 42-day mortality rate of IYIs were 0.199 and 0.095 per 1000 patient-days, respectively. The 42-day case-fatality rate remained high at 47.7%. In categorical analysis, age >65 years, corticosteroid use, elevated lactate (>2 mmol/L), neutropenia (<500/mm³), vasopressor use, and mechanical ventilation were more common in non-survivors. Primary bloodstream infections were more frequent in non-survivors, whereas catheter-related and abdominal-origin infections were predominant among survivors. Concomitant bacteremia was observed in 32.6% of IYI cases (n = 63), with <i>Enterococcus faecium</i> being the most frequently isolated co-pathogen. Our findings illustrate the evolving epidemiology of IYIs in hematologic patients, marked by the emergence of <i>C. tropicalis</i> as the predominant species, sustained mortality, and frequent bacterial co-infections, collectively reflecting the substantial clinical burden of IYIs.