16
Î Hepatitis B or C can be associated with urticarial vasculitis and should
be considered in the differential diagnosis, particularly for patients
whose behaviors predispose to contracting a sexually transmitted
disease, who have recently received a blood transfusion, or who have
exposure to contaminated needles. (C)
Î Bullous pemphigoid can present initially with urticaria-like papules or
small plaques that can be excoriated by the patient before noticeable
blistering occurs. (D) (Table 7)
Î Persistent swelling of the lips without evidence of eczematous
dermatitis might be a sign of cheilitis granulomatosa (Melkersson-
Rosenthal syndrome). (C)
Î Polymorphous light eruption differs from solar urticaria in that onset
usually occurs minutes to hours after sunlight exposure, and the
eruption lasts for days compared with solar urticaria, which is short-
lived between exposures. (D)
Î Recall urticaria is a condition in which urticaria is observed at the site
of a previous sting or injection after re-exposure to the same inciting
factor. (C)
Table 5. Causes of Autoantibody-associated Urticaria,
Angioedema, or Both
Autoantibody to C1q, C1-inhibitor
Autoantibody to IgE or IgE receptor
Cryoglobulinemia
Cutaneous and systemic lupus erythematosus
HUVS
Lymphoreticular malignancy
Still disease
Table 6. Other Dermatologic Diseases Presenting
with Urticaria
Atopic dermatitis
Bullous pemphigoid
Contact dermatitis (type IV hypersensitivity)
Dermatitis herpetiformis
Gestational pemphigoid
Papular urticaria from reduviid bite, fire ant sting
Still disease
Differential Diagnosis
