Utility of IgE (total and Aspergillus fumigatus specific) in monitoring for response and exacerbations in allergic bronchopulmonary aspergillosis

The role of total and specific IgE in monitoring treatment responses in allergic bronchopulmonary aspergillosis (ABPA) remains poorly studied. Here in, we evaluate the utility of total and Aspergillus fumigatus specific IgE in the follow-up of ABPA. Eighty-one consecutive treatment-naive patients of ABPA (acute stage) with pulmonary infiltrates and bronchiectasis underwent measurement of total and A. fumigatus specific IgE at baseline, after 8 weeks of glucocorticoid therapy, and during exacerbations. There was clinical and radiological improvement after treatment with median decline of total IgE by 51.9%. The total IgE declined by at least 35%, 25% and 20% in 69 (85.2%), 76 (93.6%) and 78 (96.3%) patients, respectively. On the other hand, the A. fumigatus specific IgE increased in 42 (51.9%) subjects, and the mean increase was 1.4%, after 8 weeks. Among 13 patients with exacerbation, 12 (92.3%) had a rise of total IgE by >50%. The A. fumigatus specific IgE increased in only five (38.5%) subjects during exacerbation. Thus, the total IgE is a useful test in monitoring treatment responses in ABPA while A. fumigatus specific IgE has limited utility.