Contact allergy

Section: Epidemiologymentioning

confidence: 99%

Section: Epidemiologymentioning

confidence: 99%

Section: Pathogenesismentioning

confidence: 99%

Section: Genetic Predispositionsmentioning

confidence: 99%

Section: Clinical Aspects Of CDmentioning

confidence: 99%

See 3 more Smart Citations

Contact dermatitis: a comparative and translational review of the literature

Campbell

Lavergne

2015

Canine dermatitis on contacting grass leaf: A case series

Mason

Ruutu

2023

Background: Pruritus is a common clinical sign in dogs for which owners seek veterinary attention. Its diagnosis and treatment are often a source of frustration for the owner and veterinarian. Contact dermatitis is rarely considered, even when lesions are located only on the skin. This report describes the immediate reaction to grass leaf material after skin exposure, with similarities to human protein contact dermatitis. Hypothesis/Objective: To describe the history, clinical findings, diagnostic methods, and characteristics of an undescribed canine pruritic dermatitis that is clinically distinct from canine atopic dermatitis and contact dermatitis. Animals: Eighteen pet dogs living in Australia were referred for unresolved pruritic dermatitis. Materials and Methods: Retrospective analysis of clinical records from patients with pruritic dermatitis after contacting grass leaves. Findings on skin testing, isolation, challenge, and description of skin lesions are described. Results: Dogs had an inflammatory and pruritic dermatitis affecting the ventral chest, anterior-medial thighs and distal limb, areas that had been in contact with grass, which dogs instinctively avoided. Erythema and erythematous macules and papules were characteristic in the affected skin, inducing coat loss, and thickened pigmented skin. Isolating the dogs from grass resolved their clinical signs and pruritus returned within hours of contact with causative grass. Conclusion and Clinical Importance:A literature review revealed that this canine dermatitis was similar to human protein contact dermatitis. The impact may be enormous for the treatment of dogs having this disease because the treatment path differs from the therapeutic options of common canine pruritic skin disorders, including the possibility of cure by avoidance.

Immunoglobulin E‐specific allergens against leaf in serum of dogs with clinical features of grass leaf allergy

Mason

Davies

Ruutu

2023

BackgroundGrass leaf has been suspected of causing immunoglobulin (Ig)E‐mediated immediate hypersensitivity reactions in humans and dogs. However, most studies in this area are case‐control studies without in vitro data showing the involvement of IgE in the reaction. Laboratory studies have demonstrated the reactivity to a 50–55 kDa protein with clinical signs immediately after contact with grass leaf material. The clinical findings of dogs with atopic‐like dermatitis immediately after contact with grass leaf material suggest the involvement of grass leaves as the allergen source.ObjectivesThis study was designed to test the IgE‐reactivity of grass leaf proteins in dogs with clinical signs and positive scratch test results against grass leaf material.Materials and MethodsThe serum of 41 patients with a history of allergy and suspected to grass leaf material was immunoblotted against grass leaf extracts from five suspected grass species. The IgE‐positive blots were separated with 2D gel electrophoresis and analysed with mass spectrometry (MS). Commercially supplied proteins were used to validate immunoblot activity.ResultsThe serum of 25 dogs diagnosed with grass dermatitis had positive IgE‐specific immunoblot against one or more grass leaf extracts. The MS data indicated a reactive band at 55 kDa to be beta‐amylase or RuBisCO (ribulose‐1,5‐bisphosphate carboxylase/oxygenase) large subunit (RbLS). All tested dog sera showed IgE‐reactivity with beta‐amylase and some with RbLS.Conclusions and Clinical RelevanceCanines with clinical signs of grass‐related dermatitis had IgE‐reactivity against grass leaf proteins. Serum IgE‐reactivity to beta‐amylase and RuBisCO large subunit may indicate that these proteins act as allergens, possibly causing pruritus and skin lesions.