A 32-year-old woman with long standing asthma has worsening cough productive of brownish mucous plugs. Chest radiograph shows fleeting upper lobe infiltrates and central bronchiectasis. Total serum IgE is 2400 IU/mL with absolute eosinophilia. Sputum culture grows Aspergillus fumigatus. Which statement best describes the pathogenesis?

• A Tissue invasion by septate hyphae invading blood vessel walls
• B Granulomatous inflammation with caseation caused by an acid fast organism
• C A fungus ball growing within a preexisting apical cavity
• D A hypersensitivity reaction to fungal antigens colonizing the airway lumen without tissue invasion ✓

Explanation

Allergic bronchopulmonary aspergillosis occurs almost exclusively in asthmatics and cystic fibrosis patients. It is a Th2 driven hypersensitivity response to A. fumigatus antigens in luminal mucus, giving elevated total IgE, eosinophilia, central bronchiectasis, and finger in glove opacities. Option A describes invasive aspergillosis of the immunocompromised host, and option C describes an aspergilloma in a preexisting cavity such as old tuberculosis. Caseating granulomas point to tuberculosis, not Aspergillus hypersensitivity.

Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.