Urticaria in Adult
Urticaria is defined as acute (new onset or recurring episodes of fewer than 6 weeks' duration) or chronic (recurring episodes lasting longer than 6 weeks). There is an increased incidence of positive thyroid autoantibodies in chronic cases. Chronic urticaria is more common in women and middle-aged individuals, whereas acute urticaria is more commonly seen in children. Disease resolves within 12 months in approximately 50% of adults with idiopathic urticaria.
Drugs causing urticaria include aspirin, nonsteroidal anti-inflammatory agents, morphine and codeine, penicillin and its derivatives, cephalosporins, sulfa, streptomycin, tetracycline, griseofulvin, blood products, radiographic contrast media, angiotensin-converting enzyme inhibitors, and sulfonylureas.
Other Associated Factors:
- Systemic illnesses such as infections, collagen vascular diseases, neoplasia, endocrine disorders, and blood dyscrasias
- Environmental stimuli such as insect stings (papular urticaria) and inhalants (pollen, spores, animal dander, perfumes, detergents)
- Foods such as strawberries, nuts, eggs, and shellfish
- Physical stimuli such as heat, cold (cold urticaria), exertion, sunlight (solar urticaria), water (aquagenic urticaria), vibration (physical urticaria), or pressure (pressure urticaria) are common causes of urticaria in adults. Vibratory urticaria has been associated with a mutation in ADGRE2 (EMR2), which affects mast cell function.
Urticaria is rarely a paraneoplastic syndrome except in the association of cold urticaria as a result of cryoglobulins associated with myeloma or lymphoma. Cold urticaria without cryoglobulins has been reported in HIV-infected individuals.
Related topics: Contact urticaria, Cholinergic urticaria, Dermographism, PUPPP, Urticarial vasculitis, Urticaria pigmentosa
L50.9 – Urticaria, unspecified
126485001 – Urticaria
- Urticarial vasculitis has lesions that persist over 24 hours and may have associated purpura.
- Dermatographism may mimic urticaria and is induced by firmly stroking the skin. It lasts from 0.5 to 2 hours.
- Contact dermatitis (irritant, allergic) may have an unusual geometric shape correlating to the inciting irritant and often develops blisters.
- Erythema multiforme typically presents with palmar and plantar targetoid plaques that last over 24 hours.
- Bullous pemphigoid and dermatitis herpetiformis may present with urticarial lesions, but individual lesions last longer than 24 hours and progress to vesicles or erosions. These are exceptionally pruritic as well.
- Herpes zoster may initially be urticarial, but lesions are painful and evolve into blisters and crusts.
- Insect bites (papular urticaria) last longer than 24 hours.
- Serum sickness can be urticarial but is accompanied by arthralgias, fever, and malaise.
- Angioedema – Edema of the subcutaneous or submucosal tissues; is not pruritic and commonly affects the face (eyelids, earlobes, lips).
- In urticaria pigmentosa, hyperpigmented lesions will urticate when stroked (Darier's sign) as histamine is released from the mast cells.
- Bedbug bite
- African trypanosomiasis