External validation of a candidaemia mortality risk predictive model in a contemporary Australian cohort

<h2>Abstract</h2><h3>Objectives</h3> A candidaemia risk prediction model by Keighley <i>et al.</i> stratified patients with candidaemia into <20% or ≥20% predicted 30-day all-cause mortality based on age >65 years, intensive care unit admission, chronic organ dysfunction, no recent surgery, haematological malignancy, source of candidaemia, and prolonged antibiotic therapy. We aimed to validate this model in a contemporary patient cohort. <h3>Methods</h3> This retrospective cohort study was conducted at a 671-bed tertiary hospital comprising both abdominal solid organ and allogeneic stem cell transplant services (Melbourne, Australia). All adult inpatients with <i>Candida</i> spp. isolated from blood cultures from 2018 to 2023 were included. Model performance was evaluated using logistic regression and area under the receiver operating characteristic curve. <h3>Results</h3> A total of 121 patients with candidaemia were identified, of whom 40 (33%) died within 30 days. The median mortality risk score was 3 (interquartile range, 2.5–4.5). The risk score demonstrated good discriminative ability in predicting mortality in our cohort (area under the receiver operating characteristic curve, 0.759), with a score of 2 providing a discriminative cut off (11% mortality score ≤2, 43% mortality score >2, and negative predictive value 89.2%). Patients aged >65 years, intensive care unit admission, and a gastrointestinal or unknown source of candidaemia were independently associated with mortality. <h3>Conclusions</h3> The candidaemia mortality risk predictive model by Keighley <i>et al.</i> performed well in our contemporary and complex patient population. This model can be utilized to risk-stratify patients into low and high mortality risk to assist with candidaemia management and antifungal stewardship.