What is the mechanism of atopic dermatitis?
Atopic dermatitis (AD) is a chronic inflammatory disease which results from complex interactions between genetic and environmental mechanisms. An altered lipid composition of the stratum corneum is responsible for the xerotic aspect of the skin and determines a higher permeability to allergens and irritants.
What is the main cause of atopic dermatitis?
The main triggers of atopic dermatitis are dry skin, irritants, stress, allergies, infection and heat/sweating. It’s important to note that these are triggers that worsen the symptoms of atopic dermatitis, and don’t necessarily cause atopic dermatitis.
What is the pathophysiologic mechanism of contact dermatitis?
The pathophysiology of allergic contact dermatitis starts with the contact of the allergen to the skin. This allergen penetrates that stratum corneum of the skin and is taken up by Langerhans cells.   The antigens subsequently undergo processing by these cells and get displayed on their surface.
What cells cause atopic dermatitis?
The specialised immune cells of the epidermis (Langerhans cells) have an increased response to these antigens in atopic dermatitis and interact with dermal T cells to produce an even greater Th2 response further exacerbating the barrier defect.
Why dermatitis is caused?
Dermatitis is caused by a combination of immune system activation, genetics and environmental triggers. Immune system. Sometimes your immune system overreacts. If you have atopic dermatitis, your immune system reacts to seemingly small irritants or allergens.
How is atopic eczema diagnosed?
No lab test is needed to identify atopic dermatitis (eczema). Your doctor will likely make a diagnosis by examining your skin and reviewing your medical history. He or she may also use patch testing or other tests to rule out other skin diseases or identify conditions that accompany your eczema.
What does atopic mean?
Atopy refers to the genetic tendency to develop allergic diseases such as allergic rhinitis, asthma and atopic dermatitis (eczema). Atopy is typically associated with heightened immune responses to common allergens, especially inhaled allergens and food allergens.
Is atopic dermatitis genetic?
The genetics of atopic dermatitis are not completely understood. Studies suggest that several genes can be involved in development of the condition. In very rare cases, atopic dermatitis is caused by inherited mutations in a single gene. One such gene is the CARD11 gene.
What is the causative agent of contact dermatitis?
Contact dermatitis is caused by a substance you’re exposed to that irritates your skin or triggers an allergic reaction. The substance could be one of thousands of known allergens and irritants. Some of these substances may cause both irritant contact dermatitis and allergic contact dermatitis.
Which immune mechanism is involved in contact dermatitis?
Allergic contact dermatitis is a classic example of a cell mediated hypersensitivity reaction in the skin. This occurs as a result of xenobiotic chemicals penetrating into the skin, chemically reacting with self proteins, eventually resulting in a hapten-specific immune response.
What type of hypersensitivity is atopic dermatitis?
Atopic dermatitis is a type I IgE-mediated hypersensitivity reaction, but the exact etiology is unknown.