Medizinische Universität Graz Austria/Österreich - Forschungsportal - Medical University of Graz
Gewählte Publikation:
Reischies, F.
Mould Infections in Patients with Hematological Malignancies: Novel Diagnostic Approaches, Standardized Urine Testing and Comparison with Serum Results
Doktoratsstudium der Medizinischen Wissenschaft; Humanmedizin; [ Dissertation ] Graz Medical University; 2017. pp. 96
[OPEN ACCESS]
FullText
- Autor*innen der Med Uni Graz:
- Betreuer*innen:
- Hönigl Martin
- Raggam Reinhard Bernd
- Altmetrics:
- Abstract:
- Recent studies on the diagnostic performance of urine Galactomannan (GM) determination for invasive aspergillosis (IA) have not taken into account urine dilution. Aim of this study was to evaluate whether a ratio of urine GM divided by urine creatinine could improve the diagnostic performance of urine GM determination. This prospective study was conducted at the Medical University Hospital of Graz, Austria, between September 2014 and August 2015.Urine samples from hematological patients at risk for invasive fungal infections (IFI) were collected twice weekly, and GM (Platelia) and Creatinine levels were determined. To normalize the GM levels against the Creatinine levels the GM-Creatinine ratio was calculated (GM level*100/Creatinine level). We evaluated the new GM-Creatinine ratio clinically by comparing it to the conventional GM optical density index (ODI). Cut-offs were determined by Youdens Index and diagnostic performance was analyzed for the GM-Creatinine rndex and the conventional GM ODI compared between IA vs. no IA cohorts and IA vs. validation cohorts. 632 samples from 71 patients were analyzed for this study. Ten patients (34 samples) were included in to the IA cohort, 61 patients (598 samples) in the cohort with no evidence for IA; 48 patients (48 samples) from an outpatient department served as a validation cohort (VC). With a cut-off at 0.26 Sensitivity, Specificity, Negative Predictive Value (NPV), Positive Predictive Value (PPV) were found to be 79.4%, 68.6%, 98.3%, 12.6%, respectively. When the IA cohort was compared to the no IA cohort ROC curve analysis showed that the area under the curve (AUC) value for the GM-Creatinine ratio was 0.801 and therefore higher than the AUC for the conventional GM ODI at 0.746. The differences between the AUC values were bigger when the IA cohort was compared to the VC with 0.792 for the conventional GM ODI and 0.913 for the GM-Creatinine ratio. The GM-Creatinine ratio allows better interpretation of detectable GM levels from urine samples and improves the diagnostic performance.