Airborne Anaphylaxis: Highlighting an Invisible Enemy

Erminia Ridolo; Cristoforo Incorvaia; Jan Walter Schroeder

Disclosures

Curr Opin Allergy Clin Immunol. 2022;22(5):283-290. 

In This Article

Abstract and Introduction

Abstract

Purpose of Review: Airborne anaphylaxis is a rare disorder defined by the occurrence of anaphylactic reactions to inhaled allergens, which may arise not only in occupational exposure but also in common settings. Foods are the most common cause of airborne anaphylaxis, even organic mixtures scents. The other important cause is represented by drugs, while in the wide range of other causes, there are often reports on unique cases. This review aims to make an overview about the potential causes of airborne anaphylaxis, by analysing what is described in literature on this topic.

Recent Findings: Concerning epidemiology, no data on specific prevalence of airborne allergy in adults are available. To date, only one study evaluated the specific prevalence of airborne allergy with anaphylaxis to foods in children, resulting in 5.9% of reactions due to exposure to aerosolized foods, compared with 78% of reactions caused by food ingestion. In addition to anaphylaxis, airborne-related reactions may also present with symptoms such as rhino-conjunctivitis, wheezing, dyspnoea and asthma.

Summary: A detailed anamnesis facilitates a correct diagnosis, which allows appropriate therapeutic and preventive interventions, but, similarly to rare diseases in general, only specialized doctors are able to implement it. The assumption of the approach used in emergency medicine for other causes of anaphylaxis, that is referring the patient at discharge to an allergist who will teach the basic notions to recognize symptoms and access the appropriate therapy, would allow the patient to avoid situations of serious danger.

Introduction

Through the vision of precision medicine, anaphylaxis is defined as the most severe and life threatening of the allergic reactions, exposing patients to serious risks and requiring rapid diagnosis and management by healthcare providers. In fact, as its symptoms are similar to those of other diseases, for example hives or asthma, recent data suggest that diagnosis is not infrequently wrong.[1] The most common causes of anaphylaxis are drugs, foods and insect stings,[2] but further sources are currently considered to be included. Airborne anaphylaxis is defined by the occurrence of anaphylactic reactions to inhaled allergens. It has long been known that such contact via inhalation can cause even severe allergic reactions, which can arise in occupational exposure as well as in common settings including household, school, restaurants and air travel.[3] Although reactions to food through ingestion are triggered by specific proteins,[4] these allergens are usually absent in the airborne component: for example, the scent of peanuts, which is contained in smaller organic mixtures, is unable to trigger a common allergic response.[5] As far as epidemiology is concerned, the most recent study reported that the prevalence of food allergy is still increasing, particularly in adults, but no data on specific prevalence of airborne allergy were provided.[6] An epidemiological evaluation of a group of children with anaphylactic reactions to foods with a median age of 7 years reported that most reactions (78%) occurred after ingestion, eight (16%) of them occurred after exclusive skin contact, and three (5.9%) occurred after exposure to aerosolized food.[7] This review aims to make an overview about the potential causes of airborne anaphylaxis (Figure 1), by analysing and bringing order to what is described in literature on this argument, for the most part consisting of case reports, whose diagnostic tests are summarized in Table 1.

Figure 1.

The main causative agents of airborne anaphylaxis.

processing....