[A CASE OF ALLERGIC BRONCHOPULMONARY ASPERGILLOSIS THAT DEVELOPED FROM DE NOVO SENSITIZATION IN A STABLE NON-ATOPIC...

A 76-year-old woman was diagnosed with asthma at 40 years of age because of chest tightness and wheezing. She was considered to have non-atopic asthma, because total and specific IgE values were normal. Combination therapy with inhaled corticosteroid and long-acting β₂-adrenergic agonist was effective. Thereafter, the patient remained asymptomatic. Chest radiograph and pulmonary function test were normal, excluding mild elevation of peripheral blood eosinophil counts (maximum value of 670/μL) during this period. At 73 years of age, the chest computed tomography (CT) performed during this stable phase showed mucoid impaction, including a high-attenuation area in the left lower lobar bronchi (B⁸, B⁹) with central bronchiectasis. These high-attenuation mucus (HAM) plugs were not visible in chest radiograph. Re-examination of the blood test revealed elevated total IgE and specific IgE to Aspergillus. Moreover, Aspergillus IgG antibody titer was positive. Therefore, the patient was diagnosed with allergic bronchopulmonary aspergillosis (ABPA). Oral corticosteroids effectively removed HAM plugs. However, HAM plugs recurred in the same bronchi after 16 months. This non-atopic patient acquired de novo sensitization to Aspergillus during a long, stable period of asthma, with HAM plugs initially identified via chest CT, which made early detection difficult.