Abstract third-party references: Mirkovič B., Lavelle G.M., Abdul Azim A. et al. The basophil surface marker CD203c identifies Aspergillus species sensitization in patients with cystic fibrosis // Journal of Allergy and Clinical Immunology. – 2016. – Vol. 137. – P.436-443., 1. Agarwal R.A., Chakrabarti A., Shah D. et al. For the ABPA complicating asthma ISHAM working group 2013. Allergic bronchopulmonary aspergillosis: review of literature and proposal of new diagnostic and classification criteria // Clinical & Experimental Allergy. – 2013. – Vol. 43. – P.850-873., Gernez Y., Waters J., Mirković B. et al. Blood basophil activation is a reliable biomarker of allergic bronchopulmonary aspergillosis in cystic fibrosis // European Respiratory Journal. – 2016. – Vol. 47. – P.177-185.
Background: Identification of fungal sensitization is important for the diagnosis of allergic bronchopulmonary aspergilosis (ABPA). Recently, much attention has been paid to in vitro methods, the advantage of which is patient safety, specificity and the possibility of standardization. To study the possibility of using the basophil activation test (BAT) with Aspergillus fumigatus allergen using flow cytometry for identification of fungal sensitization in asthma patients.
Materials/methods: In prospective study included 76 severe asthma patients with median age 36 years (23 – 78). All patients underwent skin tests with six fungal allergens, determination of total IgE, specific serum IgE to fungal, domestic and epidermal allergens level (by enzyme immunoassay) and BAT by flow cytometry (Allergenicity kit, Beckman Coulter, USA). For basophil stimulation were used allergens A.fumigatus (AlcorBio, Russia). ABPA diagnosis was made according R. Agarwal et al (2013) criteria.
Results: Severe asthma with fungal sensitization (SAFS) was detected in 17 patients, severe asthma without fungal sensitization (SAwFS) - 39, ABPA – 20.
The amount of activated basophils A. fumigatus allergen in patients with ABPA was 81.9 (53,1-93,0) %.
The stimulation index (IS) in patients with ABPA was significantly higher 21.6 (18.0-32.2) compared with patients with SAFS and SAwFS: 4.4 (1.9-16.3) and 1.0 (0.8-1.4), p = 0.001, p = 0,000, respectively.
To evaluate the diagnostic value of IP in the detection of fungal sensitization, a ROC analysis was performed. The area under the curve (AUC) was 0.94, the sensitivity and specificity was 86.1% and 89.7%, (p<0,0001). The optimal cut‐off value for IP was 2.55.
Among all patients with fungal sensitization, a direct correlation was found between IgE and the percentage and absolute number of eosinophils (r = 0.42, r = 0.46, p <0.05), the level of sIgE to A. fumigatus (r = 0.47, p <0.05), the percentage of basophils activated by the allergen A. fumigatus (r = 0.41, p <0.05) and IP (r = 0.41, p <0.05), as well as the inverse correlation with FVC (r = - 0.35, p <0.05).
Conclusions: Basophil activation test is a promising method for the laboratory diagnosis of fungal sensitization.
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Full conference title:
- ECCMID 30th (2020)