Journal Scan: The pathophysiology of canine atopy: How a better understanding can lead to better treatment
What they did
What they found
It is now recognized that AD can occur even in the absence of allergen-specific IgE and that, conversely, allergen-specific IgE concentrations can be detected in dogs that do not have clinical manifestations of AD. Other factors such as T cell subpopulations, altered mast cell releasability, and defective skin barrier function may also contribute to the pathogenesis of AD.
Histamine as a mediator of pruritus in canine AD has also been challenged in recent studies. Cytokines and leukotrienes are being actively studied as contributors to the inflammatory response in patients with AD. Ultrastructural changes in the skin surface have also been documented in dogs with AD, which may predispose percutaneous allergen exposure. Whether AD is caused by a primary immune defect or the result of a defect in the skin barrier is still a matter of debate according to the review authors.
The authors also state that with this new information, it will eventually be possible to develop safer and more effective treatments that target AD at many points in the cycle.
Marsella R, Sousa CA, Gonzales AJ, et al. Current understanding of the pathophysiologic mechanisms of canine atopic dermatitis. J Am Vet Med Assoc 2012;241(2):194-203.