Role of <b><i>Aspergillus fumigatus-</i></b>Specific IgE in the Diagnosis of Allergic Bronchopulmonary Aspergillosis

Abstract

Introduction: Allergic bronchopulmonary aspergillosis (ABPA) has been regarded as a rare disease in China due to the lack of quantitative detection of Aspergillus fumigatus-specific IgE (sIgE). We compared the diagnostic rate of ABPA among asthma patients with or without A. fumigatus-sIgE screening tests to evaluate the benefit of the tests in diagnosing ABPA. Methods: We reviewed the detection rate of A. fumigatus-sIgE and the diagnostic rate of ABPA in 1842 asthma patients in the First Affiliated Hospital of Zhejiang University from 2014 to 2016. Additionally, we collected 144 asthma cases from November 2016 to March 2017 to detect the total serum IgE, A. fumigatus-sIgE and sIgE against mixed mold extract, the ABPA diagnostic rate of these patients was then compared with the total cohort. Total serum IgE, A. fumigatus-sIgE and sIgE against mixed mold extract were also tested in 30 patients identified with Aspergillus-positive sputum culture to analyze the incidence of ABPA. Results: Among the 1,842 asthma cases, 566 were inspected for total IgE; 308 (55.40%) were total IgE-positive and 58 (10.43%) had total IgE > 1,000 IU/mL. In contrast, only 126 cases were tested for A. fumigatus-sIgE (6.84%), and 28 had A. fumigatus-sIgE > 0.35 kUA/L (22.22%). Eleven patients were finally diagnosed with ABPA. Of 1,842 asthma patients, only 0.6% were diagnosed with ABPA if the A. fumigatus-sIgE was not detected at first. Moreover, among the 144 asthma cases that were selected for total IgE, A. fumigatus-sIgE, and sIgE against mixed mold extract screening tests, 12 had total IgE > 1,000 IU/mL (8.33%), 11 had A. fumigatus-sIgE > 0.35 kUA/L (7.64%), and 14 had sIgE against mixed mold extract > 0.35 (9.72%); 7 of these patients were confirmed as having ABPA according to the ISHAM guidelines (4.86%) but only 2 without A. fumigatus-sIgE screening test were diagnosed with ABPA (1.39%) (p = 0.000). Of the 30 Aspergillus-positive sputum culture cases, 4 had A. fumigatus-sIgE > 0.35 kUA/L (13.33%), but none was diagnosed with ABPA. Conclusions: Routine A. fumigatus-sIgE screening for asthma patients can significantly improve the diagnostic rate of ABPA.

Diagnosis of allergic bronchopulmonary aspergillosis in patients with persistent allergic asthma using three different diagnostic algorithms

“…In our study, 32.5% of patients with PAA showed tIgE ≥417 and six patients (3.0%) all with ABPA had tIgE >1000 IU/ml with a mean of 1187.5 IU/ml. A higher rate of tIgE >1000 IU/ml (10.43%) in comparison with our study was reported by Lou et al 20 in patients with asthma. Similarly, some previous studies have also shown a higher level of tIgE in ABPA patients 17,21 …”

“…In this present study, 22 (11.0%) patients with PAA showed sIgE Af values >0.35 kUA/L of which 50.0% cases with ABPA diagnosis. A report by Lou et al 20 showed a higher rate of sIgE Af (22.2%) in asthmatic patients. However, our finding was in line with Sarkar et al 22 and Prasad et al 23 The sIgE Af value as one of the most sensitive and specific parameter in ABPA diagnostic criteria along with Aspergillus skin test make algorithm A as the most widely used criteria for ABPA diagnosis 19 …”

“Allergic Bronchopulmonary Aspergillosis: Radiological and Microbiological Profile of Patients Presented in an Outpatient Pulmonary Clinic of a Developing Country”.

“…of ABPA patients are also reported to have an absolute eosinophil count of <500 cells/mm³ [17] , which may possibly be attributed to the use of drugs prior to diagnosis which may have reduced blood eosinophil levels. In our study, we measured the differential eosinophil count which was found to have a mean value of 11.2 ± 7.7%.…”

The Importance of a Complete Clinical History: The Vision of the Patient as a Whole

“…In addition, the clinical history and studies conducted lead to a bird-egg syndrome [5,6]: Diagnosed of asthma for about 20 years, in the context of respiratory allergy to feathers of the birds that she had as pets. In the evolution of their basic allergic pathology, food allergy to eggs, contact urticaria to raw chicken [7] and ABPA (Allergic Bronchopulmonary Aspergillosis) have appeared [8,9]. It meets criteria for ABPA (diagnosis of asthma, positive IgE for Aspergillus, elevation of total IgE, serum precipitins against Aspergillus, bronchiectasis) which aggravates its bronchial respiratory pathology [10,11].…”