Defining the Threshold Duration of Candidemia Associated With Poor Outcomes: Redefining Persistent Candidemia

Objectives Persistent candidemia is traditionally defined as ≥5 days of positive blood cultures (BC), although emerging evidence suggests that earlier clearance may influence outcomes. We aimed to identify an earlier threshold associated with 30-day mortality to enable timely interventions and to explore predictors of its occurrence. Methods Single-center retrospective study evaluating the frequency and prognostic impact of persistent Candida spp. bloodstream infection. Persistent candidemia was defined using follow-up positive blood cultures (FUPBC) and after initiation of active antifungal therapy (FUPBC-ATF). The primary objective was the earliest FUPBC and FUPBC-ATF thresholds predicting 30-day mortality after adjusting for relevant variables, and the secondary objective was the identification of predictors that may predict its occurrence. In both cases, a multivariable logistic regression was applied. Results A total of 493 patients with candidemia were analyzed. The earliest cutoffs associated with increased adjusted 30-day mortality were ≥2 days for FUPBC (37.9% vs. 20.3%, p=0.001) and ≥1 day for FUPBC-ATF (33.4% vs. 20.3%, p=0.026). Additional variables associated with 30-day mortality were septic shock and neutropenia. Factors associated with persistence included female sex, cancer, total parenteral nutrition, mechanical ventilation, abdominal source, and rapid time-to-positivity, whereas primary candidemia and N. glabratus were protective. Conclusion Persistent candidemia was associated with 30-day mortality. A duration ≥2 days provides the earliest and most informative cutoff for predicting 30-day mortality. This threshold allows clinicians to rapidly identify high-risk patients and take timely interventions to mitigate adverse outcomes. We propose that an earlier cutoff could better define persistent candidemia.