Food and Respiratory Allergy in Children

Review Article

Austin Therapeutics. 2016; 3(1): 1023.

Food and Respiratory Allergy in Children

Cantani A*

Division of Allergy and Clinical Immunology, Department of Pediatrics, University of Roma “La Sapienza”, Italy

*Corresponding author: Arnaldo Cantani, Division of Allergy and Clinical Immunology, Department of Pediatrics, University of Roma “La Sapienza”, Roma, Italy

Received: December 10, 2015; Accepted: January 05, 2016; Published: January 13, 2016

Abstract

Asthma is one of the most common respiratory manifestations in children and sometimes is provoked by food allergens with two mechanisms: ingestion or inhalation Clinical evidence acquired in recent year’s shows that the role of foods in asthma is far from being clear, while Food Allergy (FA) is well known as one of the leading causes of atopic disease. FA-induced manifestations ranges from urticaria, abdominal pain and anaphylaxis, but above all FA can trigger Atopic Dermatitis (AD). It may be speculated that, as in AD, food allergens could induce a cutaneous hyper reactivity comparable to the Bronchial Hyper Reactivity (BHR) reported in allergic children with asthma. Eosinophils, as in asthma, seem to have a major role in inducing and maintaining skin lesions. These observations suggest that the characteristic AD chronic skin lesions can be initiated, amplified and perpetuated by immunologic and nonimmunologic factors acting in various ways and at different levels, thus starting a vicious circle, resulting in different, though synergistic, reactions. Studies have suggested a possible link between inflammatory mediators and food-induced asthma that can be distinguished from asthma with FA. Nonspecific stimuli can have a role in triggering and worsening skin lesions, however they may play a first part in the induction of BHR. Epidemiologic studies should investigate both facets of the problem, such as asthma with FA and food-induced asthma in children. Personal data on the prevalence of respiratory symptoms in children with FA will be analyzed. We suggest considering in young children food as one of causes of asthma.

Keywords: Food allergy; Asthma; Atopic children; Epidemiology; Cutaneous hyper reactivity; Bronchial hyper reactivity

Introduction

Although FA is accepted as one of the causes of a number of atopic disorders, such as AD, acute urticaria, vomiting, diarrhea, and systemic anaphylaxis, its role in asthma appears to be less clear.

In this paper we shall briefly review the current knowledge on food induced asthma, and we shall present some personal data on the prevalence of respiratory symptoms in children with FA.

Definition and Diagnosis

Correct definition of FA is a prerequisite for effective communication in scientific circles, and for comparison of the results of different studies. Appropriate definition of FA is mandatory to establish both the prevalence of hypersensitivity to a given food and the role of FA in asthma. There is a general agreement that FA is defined as a group of symptoms occurring locally, in the gastrointestinal tract, or in remote organs as a result of an immunologic reaction. Different immunologic reactions may be involved in the clinical manifestations of FA, but the immunologic reaction easiest to demonstrate routinely is the IgE-mediated reaction. Immune complexes, as well as neutrophil chemotactic factor, have been detected in some patients with food induced asthma following the challenge test with the relevant allergen [1,2].

Allergen extracts currently available for skin testing to foods are not standardized, and their stability is usually poorly determined. For allergen ex-tracts that are rapidly degraded like those of fruits and legumes, skin tests may be falsely negative in food-allergic patients. Conversely, some extracts may contain irritating substances, causing false positive skin tests. The titration of food-specific IgE is available only for certain foods, and in contrast with better characterized inhalant allergens, the sensitivity of the test is not yet known for most unpurified food allergens. Moreover, as in inhalant allergen sensitivity, the presence of food IgE in serum does not always correlate with symptoms [3]. Symptomatic hypersensitivity is present when symptoms occur during food ingestion and a specific immune response can be shown. Asymptomatic hypersensitivity exists when no symptom occurs during food ingestion but a specific immune response can he shown (Table 1). Double-Blind Placebo-Controlled Oral Food Challenge (DBPCFC) is considered the “golden standard” for the diagnosis of FA in patients enrolled in research studies or in clinical trials [4].