Infantile Hypersensitivity Pneumonitis as a Reaction to Organic Antigens

A child with allergic bronchopulmonary aspergillosis had immunofluorescent demonstration of antibody, complement, and Aspergillus fumigatus antigen in sites of Arthus vasculitis in resected lung. This case, demonstrating features of both extrinsic allergic alveolitis and allergic bronchopulmonary aspergillosis, suggests that hypersensitivity pneumonitis is a disease spectrum, and that its manifestations depend on variations in the host response and site of reaction with antigens.