Food allergy dermatitis is most common cause of canine pruritis (itching) and skin lesions after atopic dermatitis. This problem is mediated by an immune reaction to a protein present in the diet of your dog. Proteins are hydrolyzed to amino acids and absorbed in the intestine; however, in certain conditions like heavy worm infestation or irritable bowel syndrome some large protein parts or peptides (more than 10000 Daltons) get absorbed in the intestinal mucosa and elicit an immune response against them.
Food allergy dermatitis cases are usually noticed in young dogs below the age of 1 year or in dogs above the age of 3 years. The primary difference of food allergy dermatitis from atopic dermatitis is nonresponsiveness to corticosteroids.
- The most important symptom is nonseasonal Pruritis which is nonresponsive to corticosteroids.
- There can be lesions on ear pinna, perioral, interdigital, inguinal or auxiliary
- Pyoderma with or without dermatitis may be present in some cases.
- Otitis (ear infection) mostly yeast otitis is only sign present in many cases.
- Some cases may have gastrointestinal problems along with dermatitis.
Management of this condition depends on identification and elimination of responsible food protein by elimination – challenge diets. The dog should be fed on diet with a novel protein source and food ingredients are added to this diet to identify the allergen protein. Care should be taken to ensure that diet fed to a dog is nutritionally balanced. There are a number of commercially available diets but most of them are not nutritionally adequate.
Another range of commercial diet that uses hydrolyzed protein as protein source are also available. Hydrolyzed proteins are actually enzymatically cleaved protein to a size less than 10000 Daltons. Smaller protein sizes do not elicit an immune response on being absorbed in the intestine. For this reason, hydrolyzed protein diets are becoming very popular among clinicians.
We will review such commercial HYPOALLERGENIC DIETS in our Product Review section.