Prospective Evaluation of the Fungitell® (1→3) Beta-D-Glucan Assay as a Diagnostic Tool for Invasive Fungal Disease in Pediatric Allogeneic Hematopoietic Cell Transplantation: A Report from the Children's Oncology Group

Authors

William R Otto
Christopher C Dvorak
Craig L K Boge
Luis Ostrosky-Zeichner
Adam J Esbenshade
Michael L Nieder
Sarah Alexander
William J Steinbach
Ha Dang
Doojduen Villaluna
Lu Chen
Micah Skeens
Theoklis E Zaoutis
Lillian Sung
Brian T Fisher

Publication Date

2-1-2023

Journal

Pediatric Transplantation

Abstract

BACKGROUND: Invasive fungal disease (IFD) is a major source of morbidity and mortality for hematopoietic cell transplant (HCT) recipients. Non-invasive biomarkers, such as the beta-D-glucan assay, may improve the diagnosis of IFD. The objective was to define the utility of surveillance testing using Fungitell® beta-D-glucan (BDG) assay in children receiving antifungal prophylaxis in the immediate post-HCT period.

METHODS: Weekly surveillance blood testing with the Fungitell® BDG assay was performed during the early post-HCT period in the context of a randomized trial of children, adolescents, and young adults undergoing allogeneic HCT allocated to triazole or caspofungin prophylaxis. Positivity was defined at the manufacturer cutoff of 80 pg/ml. IFD was adjudicated using blinded central reviewers. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for the Fungitell® BDG assay for the outcome of proven or probable IFD.

RESULTS: A total of 51 patients (out of 290 patients in the parent trial) contributed blood specimens. In total, 278 specimens were evaluated. Specificity was 80.8% (95% confidence interval [CI]: 75.6%-85.3%), and NPV was over 99% (95% CI: 86.8%-99.9%). However, there were no true positive results, resulting in sensitivity of 0% (95% CI: 0.0%-84.2%) and PPV of 0% (95% CI: 0.0%-6.7%).

CONCLUSIONS: Fungitell® BDG screening is of limited utility in diagnosing IFD in the post-HCT period, mainly due to high false-positive rates. Fungitell® BDG surveillance testing should not be performed in children during the early post-HCT period while receiving antifungal prophylaxis as the pretest probability for IFD is low.

Keywords

beta-D-glucan, hematopoietic cell transplantation, invasive fungal disease, sensitivity, specificity