Food Allergies and Food Intolerances

Food allergies have become increasingly more common and problematic in adults and children and are thought to affect 40% of the population.

Clinical manifestations can range from mild rashes to life-threatening anaphylaxis, the underlying immunologic pathways being either IgE-mediated or non-Ig£ meadiated (IgG, IgA and IgM)

Some reactions can be immediate while others delayed which often makes specific diagnosis troublesome.

Delayed food sensitivity has been associated with a range of disorders such as Multiple Sclerosis, Autism and Rheumatoid Arthritis.

Patients presenting with symptoms of migraine, mood swings, fatigue, intestinal upset, joint pain, high blood pressure and attention problems are often found to have delayed immune reaction to food antigens.

Distinct from Food Allergy, Food Intolerance describes foods or food components that elicit reproducible adverse reactions but do not have established or likely immunologic mechanisms and are therefore not considered food allergens – i.e. non IgE mediated. For example, one may be allergic to cow’s milk due to an immunologic response to the milk protein, or alternatively, that individual may be intolerant to milk due to an inability to digest the sugar lactose. In this instance, the milk protein is considered an allergen because it triggers an adverse immunologic reaction. In the latter, however, the inability to digest lactose leads to excess fluid build up in the GI tract (often causing  abdominal pain and diarrhea).This condition is thus termed lactose intolerance, and lactose is not an allergen because the response is not immune based.

In the past, methods used to diagnose food allergies consisted of clinical history, Skin-prick tests, analysis of a specific IgE class antibody from blood and the gold standard ‘food challenge” which is extremely difficult to perform, particularly for children.

As mentioned, it is now known that delayed hypersensitivity reactions are not restricted to IgE-mediated reactions alone, but that there are many different mechanisms that can give rise to these allergy symptoms. There is therefore a marked discrepancy between those displaying allergy reactions, and those with traditionally diagnosed food allergy.

Genova Diagnostics now offers an advanced allergy assay that provides a powerful tool for the detection of adverse reaction to food and additives. By measuring the cellular reaction to food allergens, both IgE mediated and non-IgE mediated reactions can be reliably detected.

Here is a list of what can be assessed with Genova Diagnostics FACTest™ – Food Allergen Cellular Test. 

Genova’s Comprehensive Food Allergy Profile combines the above Food Allergen Cellular Test with an IgE Food Panel Test and the Celiac Marker tTgA.

Coeliac Profile – (Gluten Sensitivity)

Test a comprehensive range of analytes to determine sensitivity to Gluten.

• Anti-Deamidated Gliadin IgA (DGP IgA)
• Anti-Endomysial IgA antibodies
• Anti-gliadin IgA antibodies
• Anti-gliadin IgG antibodies
• Anti-Tissue Transglutaminase IgA antibodies
• Total IgA