Cutaneous Adverse Food Reaction (CAFR) is caused by an allergy to a component of the pet’s food. The food allergies tend to be towards the proteins present in food. In dogs, the most common allergy is to beef, followed by soy, chicken, milk, corn, wheat and eggs. In cats, allergies to beef, dairy and fish are most common. Usually there is prior exposure to the particular food in order to develop an allergy to it. This means that the food allergy will likely be something that has been in your pet’s diet for a while.
Clinically, Cutaneous Adverse Food Reactions are difficult to distinguish from other types of allergies, such as Atopic Dermatitis. CAFR is recognised as a potential cause of non-seasonal pruritis (itching) and occasional gastrointestinal signs in dogs and cats. The clinical signs that you might see with CAFR are very similar to atopic dermatitis and the distribution of lesions and areas affected may range from just ear inflammation to whole body itching. However, the rump, under the tail, axilla (armpits) and groin are frequently affected. Some pets may have concurrent gastrointestinal signs such as vomiting, diarrhoea and flatulence. A common presentation in cats is localised pruritis around the neck and face, however it can also be generalised.
Similar to Atopic Dermatitis, these patients are very prone to secondary bacterial and yeast infections. The presence of these secondary infections can complicate reaching a definitive diagnosis and can make management of these cases a bit more difficult.
Food allergies cannot reliably be tested for with blood tests. To determine whether a food allergy is present, an elimination diet trial must be performed. This consists of feeding your pet either a hydrolysed diet from your veterinarian, or a home cooked diet that contains ingredients that your pet has not had previous exposure to (a novel diet). The trial should be continued for 8-12 weeks. When doing a food trial, you may need to discuss with your veterinarian alternative non flavoured parasite prevention to avoid possible contamination with a food type that you are trying to avoid.
At the end of the 8-12 week period, if the itching stops, then beef, chicken and other food can individually be reintroduced to see which food type your pet reacts to. A diet that avoids the specific allergen can then be chosen for long term use. It is important that the long term diet chosen for your pet is a complete and balanced diet.
The prognosis for CAFR is good once the food allergen has been identified and can be avoided. Occasionally, animals may experience further dietary intolerances and may require repeat elimination trials, as they can over time become intolerant to other foods.