Food hypersensitivity by inhalation

While much focus has been given to food hypersensitivity reactions following oral ingestion, reactions by skin contact and inhalation have slowly gained interest. Food allergy by the non-ingestant route is probably under-recognized and under-reported. This review provides a summary of the relevant studies and selected case reports on food allergy by inhalation and suggestions for management.Persons who come into contact with food, in either occupational or non-occupational settings, can inhale food particles that may lead to adverse reactions in highly sensitive individuals, or may cause de novo sensitization. Although the degree of exposure to food allergens is a major factor, concomitant environmental exposures to non-specific irritants can enhance the reactivity of the respiratory tract [1]. Exposure settings that may lead to reactions are listed in Table 1 and foods that have been implicated are listed in Table 2. Given the unpredictability and variety of these exposures, their identification by patients and clinicians can be challenging.Inhalation of food allergen depends on its airborne presence. This can occur, for instance, from the release of wet aerosols of snow crab allergens when they are "cracked" in seafood processing plants [2]. Processing of a food, such as boiling, steaming, or frying, can also release significant quantities of particulates into the air. This aerosolization has also been identified as a potential high risk factor for sensitization by inhalation [3]. In many patients, the reaction is dose-dependent [4].In the majority of patients, food particle inhalation induces respiratory symptoms that can be nasal (rhinorrhea, sneezing, nasal congestion), ocular (tearing, redness, irritation), or lower respiratory (cough, wheeze). In addition, skin manifestations and even, although much more rarely, anaphylaxis can occur.Rhinoconjunctivitis is a common complaint associated with allergy to food by inhalation. Rhinitis and/or conjunctivitis may be