248. Thirty-Day Mortality Among Patients with Candidemia Diagnosed by T2Candida Assay Alone: Influence of Risk Factors and Candida Species

Abstract

Abstract Background Candidemia is a common cause of healthcare-associated bloodstream infection with high mortality rates despite antifungal therapy. Risk factors include prolonged ICU stay, immunosuppression, and exposure to broad-spectrum antibiotics. Blood cultures (BC) remain the gold standard for diagnosis but lack sensitivity and can take days to result. T2Candida (T2C) is a rapid diagnostic test utilizing PCR and magnetic resonance technology to detect five Candida species in whole blood in less than 6 hours. In this study we examined characteristics of patients with positive T2C assays in the absence of positive BC including risk factors and 30-day mortality rates. Methods We conducted a retrospective analysis of positive T2C cases at UAB Medical Center from 2016 to 2018 with either negative or no BC. For each patient we determined if clinical signs (e.g., hypotension, leukocytosis) and risk factors for candidemia were present at the time of collection. Our primary outcome of interest was 30-day mortality. Data were compared by multivariate analysis. Results A total of 173 patients with T2C positivity alone were included in the analysis. The most common risk factor was the use of broad-spectrum antibiotics followed by CVC (Table 1). The mean number of risk factors per patient was 3.6 (Figure 1). Overall 30-day mortality was 41%. Patients with a T2C result of C. albicans/C. tropicalis were almost 2.5 times more likely to die at 30 days (aOR 2.401, CI 1.159–4.974) compared with those with other positive results. Increasing number of risk factors (aOR 1.457, CI 1.126–1.886) and increasing age (aOR 1.052, CI 1.026–1.079) were significantly associated with increased odds of death at 30 days (Table 2). Conclusion In this study we demonstrate a significant association between increasing number of risk factors, older age, and A/T result with higher odds of 30-day mortality among patients with T2C positivity alone. While concern for false-positives exists when using T2C, our data suggest that this is an acutely ill population which warrants early and aggressive antifungal therapy. The lower limit of detection of T2C (1 cfu/mL) as compared with BC may explain lack of paired positive cultures in these patients despite clinical signs of and risk factors for candidemia. Disclosures All authors: No reported disclosures.