Evaluation of aspergillus-specific lateral-flow device test using serum and bronchoalveolar lavage fluid for diagnosis of chronic pulmonary aspergillosis

Abstract

The Aspergillus-specific lateral-flow device (AspLFD) test is a newly developed point-of-care diagnostic method for invasive pulmonary aspergillosis. However, evidence of the diagnostic performance of the AspLFD for chronic pulmonary aspergillosis (CPA) is limited. Therefore, we conducted a retrospective study to investigate this in comparison with the galactomannan (GM) β-D-glucan (BDG) test. Fifty patients with chronic pulmonary aspergillosis and 65 patients with respiratory disease, as a control, were enrolled in this study. The majority of the CPA disease entities were chronic pulmonary aspergillosis (64.0%, n=32), followed by subacute invasive pulmonary aspergillosis (IPA) (20.0%, n=10) and simple pulmonary aspergilloma (SPA) (16.0%, n=8). The sensitivity and specificity of the AspLFD test in serum samples were 62.0% and 67.7%, respectively. The GM test (cutoff index, 1.54) showed a sensitivity of 22% and a specificity of 92.3%, while the sensitivity and specificity of the BDG test (cutoff, 19.3 pg/ml) were 48% and 90.8%, respectively. In bronchoalveolar lavage fluid samples, the AspLFD test showed a sensitivity of 66.7% and a specificity of 69.2%, while those of the GM test (cutoff index, 0.6) were 72.7% and 83.1%, respectively. The Aspergillus precipitating antibody test had 70% sensitivity. Unlike the Aspergillus precipitating antibody test, the AspLFD on serum samples showed similar sensitivity to non-fumigatus Aspergillus species. Patients with false-positive results for the AspLFD on serum samples were of a significantly higher age and had a higher prevalence of cavitary lesions in chest computed tomography than patients with negative results in the control group. Given the results in this study, the performance of the AspLFD using serum was acceptable as a point-of-care test for the diagnosis of CPA.