atopic dermatitis Flashcards
the most common chronic
relapsing skin disease seen in infancy and childhood
Atopic dermatitis (AD), or eczema,
It affects ____ of children worldwide and frequently occurs in families with other atopic diseases, such as asthma, allergic rhinitis, and food allergy.
10-30%
Infants with AD are predisposed to development of allergic rhinitis and/or asthma later in childhood, a process called
“the atopic march.”
AD is a complex genetic disorder that results in
a defective skin barrier,
reduced skin innate immune responses
exaggerated T-cell responses to environmental allergens
microbes that lead to chronic skin inflammation
Acute AD skin lesions are characterized by
spongiosis,
spongiosis,
marked intercellular edema, of the epidermis
dendritic antigenpresenting cells in the epidermis, such as Langerhans cells, exhibit surface-bound
immunoglobulin (Ig) E molecules.
These antigenpresenting
cells play an important role in cutaneous allergen presentation to
T-helper type 2 (Th2) cells
There is a marked___ macrophages in
acute AD lesions.
perivenular T-cell infiltrate
are found in normal numbers but in different
stages of degranulation.
Mast cells
chronic, lichenified AD is characterized
by a
hyperplastic epidermis with hyperkeratosis, and minimal spongiosis
There are predominantly IgE-bearing Langerhans cells in the
epidermis
There are predominantly macrophages in the
dermal mononuclear cell infiltrate
____numbers are increased, contributing to skin
inflammation.
Mast cell and eosinophil
Two forms of AD
Atopic eczema, Nonatopic eczema
Two forms of AD
Atopic eczema, Nonatopic eczema
is associated
with IgE-mediated sensitization
atopic eczema
is associated
with IgE-mediated sensitization
atopic eczema
aropic eczema occurs in ___ of px with atopic dermatitis
70-80%
is not associated with IgE-mediated sensitization and is seen in 20-30%
of patients with AD
non atopic eczema
non atopic eczema is not associated with IgE-mediated sensitization and is seen in___
of patients with AD
20-30%
Both forms of AD are associated with
eosinophilia
In atopic eczema, circulating T cells expressing the skin homing receptor _____produce increased
levels of Th2 cytokines, including interleukin (IL)-4 and IL-13, which induce isotype switching to IgE synthesis
cutaneous lymphocyte-associated antigen
In atopic eczema, circulating ____expressing the skin homing receptor cutaneous lymphocyte-associated antigen produce increased levels of Th2 cytokines, including interleukin (IL)-4 and IL-13, which
induce isotype switching to IgE synthesis
t cells