Is bronchial thermoplasty safe in allergic bronchopulmonary aspergillosis or severe asthma with fungal sensitization?

Abstract

© The Author(s) 2021. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http:// creat iveco mmons. org/ licen ses/ by/4. 0/. The Creative Commons Public Domain Dedication waiver (http:// creat iveco mmons. org/ publi cdoma in/ zero/1. 0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data. We read with interest the case presented by Sasada et al., describing the occurrence of aspergillosis in a patient who underwent bronchial thermoplasty (BT) [1]. The isolation of Aspergillus fumigatus, the presence of elevated serum total IgE, and possible eosinophilic inflammation (high FeNO) suggest allergic sensitization to A.fumigatus. However, the diagnosis remains unproven as specific IgE or skin test against A.fumigatus was not performed in the index case. The authors mention that there was a remarkable improvement after BT. With only two sessions of BT being completed, the observed improvement is likely the effect of itraconazole therapy. Itraconazole offers excellent results in patients with severe asthma with fungal sensitization (SAFS) and allergic bronchopulmonary aspergillosis (ABPA) [2, 3]. The absence of bronchiectasis on computed tomography does not rule out ABPA and therefore, immunological investigations are required [4]. The prevalence of Aspergillus sensitization is about 28% in asthmatics and maybe as high as 50% in those with severe asthma [5, 6]. There is a significant burden of fungal allergy in Japan. In a recent Japanese study of 124 subjects with SAFS, 29% had allergic sensitization to at least one fungus, and sensitization to A.fumigatus was seen in 11% [7]. With such a high prevalence of fungal allergy in Japan, it would be reasonable to exclude SAFS or ABPA before BT. BT is a valuable addition in severe asthma management, especially for those who are not candidates for oral glucocorticoids or biologic therapy. Nevertheless, a thorough evaluation of coexisting conditions or complications is an indispensable component while evaluating severe asthma [8, 9]. Further, the trials evaluating BT or biologics in asthma have not included subjects with SAFS or ABPA. Hence, extrapolating the results beyond the trial population may be problematic. Thus, the index case should serve as a reminder to systematically evaluate severe asthma before contemplating treatment with newer modalities such as BT.