FOOD ALLERGY

Allergic reactions to foods e.g. animal proteins, chemical additives, etc. may manifest in the form of diarrhea, rhinitis, urticaria, asthma, anaphylaxis and the like.

common offending coloring additives used in foods and additives are tartrazine, sunset yellow, cermoisine and amaranth. These additives may cause hyperactive behaviour over and above atopy.


The possible mechanisms of such adverse reactions to food include:

1. IMMUNOLOGIC IgE-mediated either toxic complex (alpha-gliadin) or cell (lymphocyte)- mediated injury;

2.Biochemical enzymes deficiency (lactase etc.), nitrate sensitivity (hog dog headache), tyramine

headache, toxic effect (alpha-gliadin);

3. Reaction to color and flavoring additives

A number of adverse reaction to whole cow milk ingestion may occur, e.g.

• Occult fecal blood loss with resultant anemia.
• Enteropathy with loss of protein and blood.
• Vomiting and diarrhea
• Heiner syndrome characterized by pulmonary hemosiderosis, chronic rhinitis, recurrent otitis media, gastrointestinal symptoms and growth failure.
• Recurrent pulmonary infiltrates in X-ray.
• Multiple precipitating antibodies.
• Disaccharide intolerance.

Diagnosis is usually by critical testing of the offending food by elimination and provocation method. Emotional bias of the parents and the child must not be allowed to operate while conducting the tests.

Skin and RAST assay may be employed to identify presence of IgE antibody to food.

Provocative/ neutralizing methods of diagnosing allergy by intradermal injection or sub lingual administration should no longer be encouraged.

Treatment is directed at elimination of the offending food. With passage of time, it becomes possible to cautiously reintroduce the offending food in to the diet as such or under cover of cromolyn sodium 60 to 200 mg (O) 30 minutes before giving food.