Atopic dermatitis, or canine atopic disease, is a hypersensitivity condition that falls under the category of allergies known as atopic. This refers to hypersensitivity towards common antigens, such as pollen diseases and food urticaria. More specifically, the term atopy is currently used synonymously with allergy or hyperergy, referring to an abnormal reactivity shown by certain individuals in response to specific antigens (defined as allergens) that are otherwise tolerated by most others.
Atopy is an inherited tendency to form excessive IgE antibodies against environmental allergens. In the case of atopic dermatitis, these allergens are primarily airborne, including pollens, molds, dandruff, hair, feathers, insects, and most importantly, dust mites. However, food allergens, chemicals found in flea saliva, and bacterial antigens (such as Staphylococcus intermedius and aureus) can also play a role.
Atopic dermatitis in dogs is mainly characterized by pruritus (itching), which primarily affects the face, feet, and abdomen. This results in behaviors such as licking the feet and scratching or rubbing the muzzle and abdomen. The condition leads to dermatitis, characterized by alopecia, hyperpigmentation, and scabs. It can be further complicated by bacterial infections, resulting in canine pyodermas. Other signs can include tearing due to allergic conjunctivitis, otitis externa, licking granulomas, and coat color changes.
Treatment of Atopic Dermatitis in Dogs
Atopic dermatitis treatment in dogs is chronic and typically lasts a lifetime. While the disease can often be controlled, it cannot usually be cured. The effectiveness of any therapeutic strategy is limited by the inability to eliminate all airborne allergens, which are the primary triggers for the disease.
Any therapeutic protocol should begin with eliminating fleas using adulticide topical products with an effect lasting at least 3-4 weeks, alongside oral products that inhibit the growth of immature fleas. It’s also crucial to eliminate fleas (both mature and immature forms) from the environment using appropriate products. Preventive measures also include treating pyoderma with systemic antibiotics and topical treatments using the correct shampoos.
The Specific Therapeutic Protocol for Atopic Dermatitis Treatment in Dogs Depends on the Nature of the Itching:
- Transient generalized pruritus: This is a seasonal disease lasting 4 months to 1 year. Treatment is symptomatic and typically involves the oral use of antihistamines and corticosteroids, either alone or in combination. Including essential fatty acids in the therapy can enhance the effects of antihistamines and corticosteroids by restoring the hydrolipidic integrity of the skin and limiting the production of pro-inflammatory compounds. A hygienic treatment with antibacterial and/or anti-itching shampoos is also beneficial.
- Localized pruritus: This is an uncommon form of atopic dermatitis, typically treated with anti-inflammatory creams, ointments, or lotions. These preparations usually contain topical corticosteroids, sometimes combined with antimicrobials, antifungals, or antiseptics.
- Chronic generalized pruritus: In such cases, treatment can involve allergen-specific immunotherapy (desensitization therapy). This consists of administering increasing doses of specific allergens (in the form of vaccines) to help increase tolerance and reduce sensitivity. These vaccines are customized based on the allergens to which a dog is sensitive. While allergen-specific immunotherapy is long-lasting, its effects are gradual, with symptom improvement typically noticed after 3-6 months. The goal is not to completely eliminate symptoms, but rather to relieve itching and reduce the need for anti-inflammatory drugs. This therapy can be combined with symptomatic treatments, such as corticosteroids and antihistamines, as well as essential fatty acid treatments.
In conclusion, atopic dermatitis is a chronic condition with a complex pathogenesis and clinical presentation. Treatment often requires lifelong adoption of multiple therapeutic strategies. It is important for the pet owner to understand that while the treatment may not provide a definitive cure, it can significantly control the symptoms and allow for a “peaceful” coexistence between the atopic dog and its condition. The effectiveness of treatment greatly depends on the collaboration and commitment of both the owner and the veterinarian.
