S4.2d Efficacy of LD Bio Aspergillus ICT lateral flow assay for serodiagnosis of chronic pulmonary aspergillosis

S4.2 ADVANCES IN DIAGNOSIS OF INVASIVE FUNGAL INFECTION, SEPTEMBER 22, 2022, 10:30 AM – 12:00 PM: BACKGROUND: The diagnosis of chronic pulmonary aspergillosis (CPA) relies on the detection of IgG Aspergillus antibody which is not freely available, especially in resource-poor settings. Point-of-care tests like LDBio, evaluated in only a few studies, have shown promising results for the diagnosis of CPA. However, no study has compared the diagnostic performances of LDBio in the setting of tuberculosis endemic countries and has compared it with that of IgG Aspergillus. OBJECTIVES: This study aimed to evaluate the diagnostic performances of LDBio in CPA and compare it with the existing diagnostic algorithm utilizing ImmunoCAP IgG Aspergillus. METHODS: Serial patients presenting with respiratory symptoms (cough, hemoptysis, fever, etc) for >4 weeks were screened for eligibility. Relevant investigations including respiratory secretions stain/culture, IgG Aspergillus, chest imaging, etc were done according to the existing algorithm. Serum of all patients was tested by LDBio and IgG Aspergillus (ImmunoCAP) and their diagnostic performances were compared. RESULTS: A total of 218 patients were screened and 174 patients were included in the study with ∼ 66.7% of patients having a past history of tuberculosis. A diagnosis of CPA was made in 74 (42.5%) patients. The estimated sensitivity and specificity of LDBio was 67.6% [95% confidence interval (CI), 55.7%-78%] and 81% (95% CI, 71.9%-81%) respectively which increased to 73.3% (95% CI, 60.3%-83.9%), and 83.9% (95% CI, 71.7%-92.4%) respectively in patients with past history of tuberculosis. The sensitivity and specificity of IgG Aspergillus was 82.4% (95% CI, 71.8%-90.3%) and 82% (95% CI, 73.1-89%); 86.7% (95% CI, 75.4%-94.1%), and 80.4% (95% CI, 67.6%-89.8%) in the whole group and those with past history of tuberculosis respectively. The baseline characteristics and diagnostic accuracies are listed in Tables 1 and 2 respectively. CONCLUSIONS: LDBio is a point-of-care test with reasonable sensitivity and specificity. However, further tests may have to be done to rule-in or rule-out the diagnosis of CPA in the appropriate setting.