A 25-year-old woman develops extensive pruritic wheals following ingestion of seafood to which she was allergic. While these lesions are usually not biopsied, a biopsy would probably show which of the following features?
Uicaria (hives) are pruritic wheals that form after mast cells degranulate and trigger localized dermal edema with dilated superficial lymphatic channels. The mast cell degranulation is sometimes, but not always, triggered by IgE-antigen interactions. Granular complement and IgG deposition at the dermal/epidermal junction is a characteristic of systemic lupus erythematosus. Microscopic blisters are a characteristic of dermatitis herpetiformis. Munro abscesses are a characteristic of psoriasis. Ref: Kaplan A.P. (2012). Chapter 38. Uicaria and Angioedema. In L.A. Goldsmith, S.I. Katz, B.A. Gilchrest, A.S. Paller, D.J. Leffell, N.A. Dallas (Eds), Fitzpatrick's Dermatology in General Medicine, 8e.
Dilated superficial lymphatic channels
Granular complement and IgG at dermal/epidermal junction
Microscopic blisters
Munro microabscesses