The Prognostic Value of (1→3)-β-D-Glucan in COVID19 Patients With and Without Secondary Fungal Diseases

Background: The presence of (1→3)-β-D-Glucan (BDG) in serum may be indicative of in-vasive fungal disease (IFD), but even without IFD elevated BDG can be associated with adverse patient outcomes. Methods: COVID-19 infected patients (n=125) who were screened for IFD with fungal biomarkers were evaluated to assess the prognostic value of BDG. BDG was correlated with patients’ mortality, while considering the influences of IFD and anti-fungal therapy (AFT). Results: A BDG concentration >31pg/mL was associated with significant mortality in the absence of documented IFD and without subsequent an-tifungal therapy (≤31pg/mL: 28% vs >31pg/mL: 91%; P = 0.0001). In patients without IFD but with a BDG >31pg/mL, mortality dropped to 50% when AFT was administered. In pa-tients with a BDG >31pg/mL, no IFD nor AFT then the average probability of death is 3.38-fold greater. Conclusions: Elevated serum BDG is associated with significant mortal-ity in COVID -19 infected patients without IFD, irrespective of AFT. A BDG associated proinflammatory response might be driving the high mortality. BDG serves as a prognos-tic marker in COVID -19 infected patients with or without IFD. When BDG is very low (≤31pg/mL) the likelihood of death remains consistent with the background morality rates for COVID-19 within the ICU.