Purpose: To assess the diagnostic utility of (1→3)-β- d -glucan (BDG) in ocular fluid of patients with fungal endophthalmitis.
Methods: This prospective pilot single-center study evaluated aqueous and vitreous humor BDG levels of suspected fungal endophthalmitis, bacterial endophthalmitis, and noninfectious controls with the standard Fungitell assay and the Fungitell STAT assay. β- d -Glucan levels were compared using generalized linear models followed by post hoc pairwise comparisons.
Results: Seven fungal endophthalmitis, 6 bacterial endophthalmitis, and 17 noninfectious ocular samples were evaluated. Mean aqueous BDG concentrations were 204, 11.0, and 9.6 pg/mL for fungal endophthalmitis, bacterial endophthalmitis, and noninfectious controls, respectively ( P = 0.01, fungal vs. bacterial; P = 0.0005, fungal vs. noninfectious controls). Mean vitreous BDG concentrations were 165, 30.3, and 5.4 pg/mL, respectively ( P = 0.001 for fungal vs. bacterial; P < 0.0001 for fungal vs. noninfectious controls). Mean vitreous BDG index (Fungitell STAT) values were 1.7, 0.4, and 0.3, respectively ( P = 0.001, fungal vs. bacterial; P = 0.0004, fungal vs. noninfectious controls). The Pearson correlation between BDG levels and BDG index was high (correlation coefficient = 0.99, P < 0.001).
Conclusion: Significantly elevated ocular BDG levels were found in fungal endophthalmitis compared with bacterial endophthalmitis and noninfectious controls. Our study suggests a potential utility for BDG testing in the diagnosis of fungal endophthalmitis, and a larger study is warranted.