Atopic Dermatitis Flashcards
An individual with atopy produces what type of antibodies specific to their allergens?
IgE
What are non-dermatologic manifestations of atopic disease?
asthma, rhinitis, conjunctivitis
True or False: All individuals with atopy (detectable IgE on a serum test) will manifest clinical signs of disease
False
True or False: All dogs with clinical atopic dermatitis will have measurable serum IgE against allergens
False
True or False: according to the ACVD Task Force definition of atopic dermatitis circa 2006, environmental allergens are the only trigger responsible for atopic dermatitis
False (their definition includes food)
What is the name for the disease in dogs with clinical signs of AD but no measurable IgE?
Atopic-like dermatitis
What is the name of the hypothesis that decreased exposure to parasites and bacteria, in conjunction with increased practices of bathing and detergents that could harm the skin barrier, are leading to increased incidence of AD?
Hygiene hypothesis
exposure to _____ has an inverse relationship with risk of developing AD, supporting the hygiene hypothesis
Endotoxin
On which human chromosomes have genes predisposing for atopic dermatitis been found?
5, 7, and 11
Two of the strongest factors for AD in humans are loss of function mutations (R501X and 2282der14) on the _______ gene
filaggrin
What is the most common name for the human manifestation of atopic dermatitis?
Eczema
Impairment of the skin’s ____ function has been documented in both human and canine AD
Barrier
In dogs or humans with decreased barrier function, will their TEWL be increased or decreased?
increased
Studies have found that atopic beagles have MORE or LESS filaggrin expression than normal controls?
less
True or False: Dogs with atopic dermatitis have higher total IgE counts than normal dogs
False (allergen-specific IgE, not total)
What subclass of IgG molecules might play an important role in AD?
IgGd
Which subtype of IgE is non-pathogenic, IgE+ or IgE-?
IgE-
True or False: it is definitively known whether allergen specific IgE development occurs before or after clinical signs of atopic dermatitis
False (we know nothing)
Classically, acute AD is associated with a Th2 response and the release of what two cytokines?
IL-4 and IL-13
In the biphasic model of atopic dermatitis, chronic lesions are characterized by cytokines of what T-helper profile (1 or 2)? What WBC predominates?
Th1 (IL-2, IL-12, IFN-y, IL-18); macrophages
Which chemokines have been associated with AD in dogs and humans?
RANTES (CCL5), eotaxin (CCL11), MCP-4 (CCL13), TARC (CCL17), CR4
Transcription/production of which cytokine has been shown to be DECREASED in dogs with AD?
TGF-B (one Japanese study also showed IFN-y)
Which cytokine, associated with eosinophil recruitment, has been found in increased levels in dogs with AD?
IL-5
Which adhesion molecule has been shown to be up-regulated in lesional skin of dogs with AD?
P-selectin
True or False: the role of histamine in canine AD is well-established
False (we know nothing)
What neurotransmitter has been shown to be important as a mediator of itch in human AD?
Serotonin
(patients treated with Bicarphen, an anti-serotonin drug, have had a good clinical response. Importance in dogs is unknown)
It is suspected that in atopic dermatitis, environmental allergens are epicutaneously captured by _____ cells, which have been shown to be increased in lesional atopic skin
Langerhans
Human atopics tend to have an increased number of ____ T cells; in addition to these, atopic dogs tend to have more ____ T cells than their human counterparts
Type 2 (alpha-beta); Type 1 (delta-gamma)
previous models of atopic dermatitis emphasized the ____ route of allergen exposure, but recent models and studies have determined the ____ route to be more important
Inhalation; Epicutaneous/percutaneous
Atopic dermatitis is typically considered a type ____ hypersensitivity reaction
Type I
True or False: clinically, reactions to food allergens may be indistinguishable from reactions to environmental allergens
True
Which environmental allergens have been shown to induce signs of AD when ingested?
Dust (and storage) mites
True or False: as in humans, self-antigens have been clearly demonstrated to play an important role in canine atopic dermatitis
False (self IgE antibodies not found in canine studies)
True or False: A direct association has been established between S. aureus superantigens and the development of human AD
True