Immunological Aspects of Respiratory Disease

THE role in respiratory tract disease of immediate allergic reactions in atopic subjects to extrinsic allergens is well known. At a meeting of this section in 1963, Dr. Gwynne Evans discussed this subject in detail. For practical purposes, allergic management, consisting of avoidance of allergens with or without attempts at hyposensitization, is applicable only to this group of patients. Nevertheless, there is long established as well as more recent evidence of the participation of other types of hypersensitivity in respiratory disease the immuno-pathology of which disease will be analysed briefly, although this will apply more to the lower than to the upper respiratory tract. Discussion of the four main types of hypersensitivity reaction is made more difficult because of their cumbersome but essential descriptions. In an attempt to simplify and clarify this, Gell and Coombs (1963) propose that they be known as Types 1 to 4.