Atopy

Atopy /ˈætəpiː/Greek ἀτοπία - placelessness, out of place, special, unusual, extraordinary) or atopic syndrome is a predisposition toward developing certain allergic hypersensitivity reactions.

Atopy may have a hereditary component, although contact with the allergen must occur before the hypersensitivity reaction can develop.

The term atopy was coined by Coca and Cooke in 1923. Many physicians and scientists use the term "atopy" for any IgE-mediated reaction (even those that are appropriate and proportional to the antigen), but many pediatricians reserve the word "atopy" for a genetically mediated predisposition to an excessive IgE reaction.

Signs and symptoms

Atopy (atopic syndrome) is a syndrome characterized by a tendency to be “hyperallergic”. A person with atopy typically presents with one or more of the following: eczema (atopic dermatitis), allergic rhinitis (hay fever), or allergic asthma. Some patients with atopy display what is referred to as the “allergic triad” of symptoms, i.e. all three of the aforementioned conditions. Patients with atopy also have a tendency to have food allergies, allergic conjunctivitis, and other symptoms characterized by their hyperallergic state. For example, eosinophilic esophagitis is found to be associated with atopic allergies.