[Clinical features and reasons for missed diagnosis of allergic bronchopulmonary aspergillosis].

ABSTRACT

Objective: To summarize the clinical features of allergic bronchopulmonary aspergillosis (ABPA) and analyze the common causes of missed diagnosis. Methods: The clinical data of patients with ABPA who were admitted into Qilu Hospital of Shandong University from October 2014 to November 2017 were retrospectively analyzed, including baseline data, eosinophil count in peripheral blood, serum total IgE, A. fumigates-specific antibody (sIgE, sIgG and sIgM), pulmonary function tests and chest CT, etc. Then the correlations between serum total IgE, sIgE and forced expiratory volume in one second (FEV1) as percentage of predicted value (FEV1%pred) was conducted, as well as that between serum total IgE, sIgE and FEV1/forced vital capacity (FEV1/FVC). The clinical features of the patients were summarized and the causes of missed diagnosis were analyzed. Results: There were 46 patients with ABPA (21 males and 25 females, 48.3±13.2 years old) in total. Only 2 cases (4.3%) were diagnosed after the first symptom onset, and 44 cases (95.7%) were treated repeatedly for many years before being diagnosed. The misdiagnoses were asthma (26 cases, 56.5%), bronchiectasis (13 cases, 28.3%), pneumonia (4 cases, 8.7%), pulmonary tuberculosis (3 cases, 6.5%), and lung cancer (4 cases, 8.7%). Common symptoms of ABPA included cough, expectoration, wheezing, chest tightness, fever, weight loss, chest pain, etc. Peripheral blood eosinophil count increased in 37 patients (80.4%). Serum total IgE in 37 patients (80.4%) were higher than 1 000 U/ml, and 9 cases (19.6%) were less than 1 000 U/ml. The positive rate of sIgE, sIgG and sIgM was 100.0%, 89.1% and 54.3%, respectively. All patients underwent pulmonary function tests and 35 cases (76.1%) had obstructive ventilation dysfunction, 5 cases (10.9%) with mixed ventilation dysfunction, 5 cases (10.9%) were normal and 1 case (2.2%) with restrictive ventilation dysfunction. All patients underwent Chest CT examination, 28 cases (60.9%) showed bronchiectasis, 8 cases (17.4%) manifested mucus plugs (among them, 4 cases with high-attenuation mucus) and 10 cases (21.7%) had other atypical imaging. Serum total IgE and sIgE had no correlations with FEV1%pred and FEV1/FVC. Conclusions: ABPA is characterized by recurrent episodes of wheezing, fleeting pulmonary opacities and bronchiectasis. The main reasons of misdiagnosis in ABPA patients were atypical symptoms, variety of predisposing diseases, early atypical imaging changes, limitations and misunderstandings of screening indicators, interference with tumor markers, and the presence of pulmonary aspergillus overlap syndrome. The severity of asthma attacks is not related to the degree of fungal sensitization.