Allergic skin diseases are very commonly seen in general practice. Reaching a diagnosis is requires correct interpretation of the clinical history and dermatological symptoms. Misdiagnosis can lead to unnecessary lifelong treatment. 

Over the last decade, new diagnostic tests for food and environmental allergens have been marketed by laboratories, yet we fail to make a definitive diagnosis in many cases. Reasons for this include a lack of standardisation in allergen selection, different methodologies and reference ranges used and lack of international standards. These all result in poor inter-laboratory comparability. Other reasons for misdiagnoses include inappropriate drug withdrawal, seasonal allergen variation and the presence of IgE antibodies against cross-reactive carbohydrate determinants etc. 

This lecture highlights the limitations of the available diagnostic tests and the drawbacks of relying on laboratory test results alone. It will discuss how to interpret test results correctly, taking into consideration the patient history, clinical signs and exposure.

Atopic dermatitis is an incurable, but a manageable, inflammatory and pruritic skin condition. It has complex pathomechanisms requiring a multimodal approach to its treatment and management. This approach includes treating and managing recurrent infections, controlling pruritus, taking preventative measures and managing owner compliance and expectations.

Depending on the severity of the clinical signs, symptomatic treatment and/or preventative measures may be implemented. Preventative measures include allergen-specific immunotherapy, maintenance of the epidermal barrier and allergen avoidance. Symptomatic treatments to manage pruritus include the use of oclacitinib, lokivetmab, glucocorticoids and ciclosporin.

Other treatments, which include prescribing antihistamines, essential fatty acid supplements, shampoo treatments and specific diets, are also used concurrently in the multimodal approach for the management of atopic dermatitis.

This lecture discusses the reactive measures when dealing with acute and chronic atopic dermatitis and taking proactive measures that could reduce the incidence and severity of flare-ups. 

Feline atopic skin syndrome is not as well defined as canine atopic dermatitis. To reach a final diagnosis of feline atopic skin syndrome, all the other causes of pruritus in the cat need to be excluded in a systematic manner. 

The syndrome is poorly defined for several reasons: 

1. It manifests in the form of reaction patterns seen in many other diseases. These reaction patterns include; miliary dermatitis, symmetrical alopecia, eosinophilic granuloma complex (that is subdivided into indolent ulcer, linear granuloma, eosinophilic plaque), and finally head and neck pruritus. 
2. Clear distribution patterns are not seen
3. The role of IgE in feline atopic dermatitis has not been fully established 

Many other conditions can result in pruritus and these reaction patterns. For example, Ectoparasites, food induced hypersensitivity dermatitis (FIHD) and flea bite hypersensitivity (FBH) can all manifest similar clinical signs.

This lecture discusses the need for a systematic approach to reach that final diagnosis of feline atopic skin syndrome. A subset of these cats may have IgE antibodies against environmental allergens where we can make that final diagnosis of atopic dermatitis.