Specific IgE Is Better Than Skin Testing for Detecting Aspergillus Sensitization and Allergic Bronchopulmonary Aspergillosis in Asthma

Abstract

We read with interest the review by Schulman et al1Schulman ES Pohlig C Rationale for specific allergen testing of patients with asthma in the clinical pulmonary office setting.Chest. 2015; 147: 251-258Abstract Full Text Full Text PDF PubMed Scopus (6) Google Scholar in a recent issue of CHEST (January 2015) wherein the authors suggest the use of a skin test for screening sensitization to various allergens in preference to specific IgE antibody testing in patients with asthma. We agree with the authors that all patients with asthma should be screened for allergic sensitization against a particular allergen depending on its prevalence. However, we do not agree with the authors' recommendation that skin testing is the preferred approach as this can potentially miss allergic sensitization against Aspergillus fumigatus. In a study comparing the performance of a skin test (intradermal) or specific IgE (against A fumigatus) for the diagnosis of allergic bronchopulmonary aspergillosis (ABPA) in 372 subjects with asthma, the sensitivity of an A fumigatus-specific IgE and Aspergillus skin test was 100% and 88% to 95%, respectively, in various models of latent class analysis.2Agarwal R Maskey D Aggarwal AN et al.Diagnostic performance of various tests and criteria employed in allergic bronchopulmonary aspergillosis: a latent class analysis.PLoS ONE. 2013; 8: e61105Crossref PubMed Scopus (120) Google Scholar Thus, if a skin test is used as a screening modality, one can potentially miss 5% to 12% cases of ABPA. It is extremely important that Aspergillus sensitization or ABPA is not missed. Aspergillus sensitization is associated with poorer lung function and worse symptoms,3Agarwal R Noel V Aggarwal AN Gupta D Chakrabarti A Clinical significance of Aspergillus sensitisation in bronchial asthma.Mycoses. 2011; 54: e531-e538Crossref PubMed Scopus (45) Google Scholar risk of death from asthma,4Targonski PV Persky VW Ramekrishnan V Effect of environmental molds on risk of death from asthma during the pollen season.J Allergy Clin Immunol. 1995; 95: 955-961Abstract Full Text Full Text PDF PubMed Scopus (249) Google Scholar and acute attacks of asthma requiring ICU admission5Black PN Udy AA Brodie SM Sensitivity to fungal allergens is a risk factor for life-threatening asthma.Allergy. 2000; 55: 501-504Crossref PubMed Scopus (247) Google Scholar; treatment with itraconazole can potentially improve the quality of life in these patients.6Denning DW O'Driscoll BR Powell G et al.Randomized controlled trial of oral antifungal treatment for severe asthma with fungal sensitization: The Fungal Asthma Sensitization Trial (FAST) study.Am J Respir Crit Care Med. 2009; 179: 11-18Crossref PubMed Scopus (297) Google Scholar Furthermore, the prevalence of ABPA in Aspergillus sensitization is about 40%,7Agarwal R Aggarwal AN Gupta D Jindal SK Aspergillus hypersensitivity and allergic bronchopulmonary aspergillosis in patients with bronchial asthma: systematic review and meta-analysis.Int J Tuberc Lung Dis. 2009; 13: 936-944PubMed Google Scholar and delay in diagnosis and treatment of ABPA can cause irreversible lung damage in the form of bronchiectasis, lung fibrosis, and, finally, end-stage lung disease and respiratory failure.8Agarwal R Chakrabarti A Shah A et al.Allergic bronchopulmonary aspergillosis: review of literature and proposal of new diagnostic and classification criteria.Clin Exp Allergy. 2013; 43 (ABPA Complicating Asthma ISHAM Working Group): 850-873Crossref PubMed Scopus (553) Google Scholar