P501 Aspergillus fumigatus complicates one third of the patients with suspected bronchial asthma or pulmonary tuberculosis: Clinical validation of indigenously developed diagnostic kits

Abstract

Objectives Aspergillus fumigatus, an opportunistic fungus, causes complications in about 5%-20% of bronchial asthma and about 26% of pulmonary tuberculosis patients. Detection of Aspergillus fumigatus specific IgG and IgE antibodies in the patient serum is an excellent tool to screen for Aspergillus sensitization early on to employ anti-fungal drugs in the clinical management to stall the progression of lung fibrosis. Methods Novel indigenous AfuPEPLISA assays were developed for the detection of specific IgG and IgE, based on the 12 amino acid long synthetic peptide epitope of Asp f1, an 18 kDa major allergen/antigen. The novel diagnostic kits were manufactured at a licensed GMP facility under a test license. Independent validation of the kits was pursued at PGIMER and VPCI hospitals in suspected bronchial asthma patients (n = 1307), and the diagnostic efficiency was compared with currently used ImmunoCAP assay. Results The diagnostic specificity and sensitivity were found to be 95.7% and 89.8%, respectively, for IgG; and 94.2% and 70%, respectively for IgE AfuPEPLISA, and were not significantly different from ImmunoCAP assay. Screening of the suspected patients of pulmonary tuberculosis (PTB) at RBIPMT Hospital for the presence of A. fumigatus specific IgG and IgE antibodies was pursued using AfuPEPLISA kits. A total of 82 out of 254 suspected PTB patients (32.3%) were seropositive in agreement with the previous reports. See Figures 1 and 2 below. Conclusion The study inferred that indigenously developed AfuPEPLISA kits are an economically viable option to integrate in the clinical management of patients with suspected bronchial asthma or PTB for efficient diagnosis of Aspergillus sensitization.