Urticaria, Angioedema And Allerhic Rhinitis Flashcards
What is atopy?
tendency to manifest asthma, rhinitis, urticaria, and atopic dermatitis alone or in combination, in association with the presence of allergen-specific IgE
Key effector cells in allergic rhinitis and asthma
Mast cells
dominant effector in urticaria, anaphylaxis, and systemic mastocytosis
Mast cells
binding of IgE to human mast cells and basophils
sensitization
Most potent known bronchoconstrictor
LTD4, acting at CysLT1 receptors
induces a vascular leak and mediates the recruitment of eosinophils to the bronchial mucosa
LTE4
Involves dilation of vascular structures in the superficial dermis,
Urticaria
originates from the deeper dermis and subcutaneous tissues.
angioedema
Urticarial lesions last for?
<24 hours
well-circumscribed wheals with erythematous raised serpiginous borders and blanched centers that may coalesce to become giant wheals
Urticaria
dramatic swelling with more pain than pruritus and minimal erythema, which may develop with a pruritic prodrome
Angioedema
takes hours to days to resolve.
Urticaria or angioedema?
Angioedema
Acute vs chronic urticaria/angioedema
Acute <6 weeks
Chronic >6 weeks
Usually idiopathic.
Acute or chronic urticaria?
chronic urticaria
linear wheal with surrounding erythema at the site of a brisk stroke with a firm object
Dermographism