Delta Neutrophil Index (DNI) as a Predictive and Prognostic factor for Candidemia patients: Matched Case-Control study

Background: Delayed antifungal therapy for candidemia leads to increased mortality. Discriminating bacterial infection from candidemia in systemic inflammatory response syndrome (SIRS) patients is very complex and difficult. Delta Neutrophil Index (DNI) is recently considered as a new factor which can distinguish infections from non-infections and reflect the severity of sepsis. We aimed to assess whether DNI can predict and provide a prognosis for candidemia in SIRS patients.Methods: A matched case-control study was conducted from July 2016 to June 2017 at Kangdong Sacred Heart Hospital. Among patients with comorbidity of SIRS, those with candidemia were classified as the case group, while those with negative blood culture results were classified as the control group. The matching conditions included age, blood culture date, and SIRS onset location. To evaluate DNI as a predictive and prognostic factor for candidemia, multivariate logistic regression was performed.Results: The 140 included patients were assigned to each group in a 1:1 ratio. DNI-D1 values measured on the blood culture date were higher in the case group ( p <0.001). In the multivariate analyses, DNI_D1 (Odds ration〔ORs〕2.138, 95% confidential interval 〔CI〕1.421-3.217, P <0.001) and Candida colonization were confirmed as predictive factors for candidemia. The cutoff value of DNI for predicting candidemia was 2.75%. The area under the curve for DNI value was 0.804 (95% CI, 0.719-0.890, p<0.001), with a sensitivity and specificity of 72.9% and 78.6%, respectively. Analysis of 14-day mortality was conducted for patients with candidemia. DNI_D1 and DNI_48, measured 2 days after the onset of candidemia, were both significantly high in the non-survivor group.Conclusion: DNI was identified to be a predictive factor for candidemia in patients wit SIRS and a prognostic factor that predicts 14-day mortality in candidemia patients. DNI, along with clinical characteristics of patients, were useful in determining the occurrence of candidemia in patients with SIRS.