Internal Medicine

0521779407-21 CUNY1086/Karliner 0 521 77940 7 June 7, 2007 18:59

Urticaria (Dermatology) 1497

➣stool for O and P, ANA, hepatitis profile, CH100, C4, C1 esterase

inhibitor level and function, thyroid function tests, thyroid

autoantibodies

➣Sinus films, chest X-ray, other radiologic studies

∗Evaluation for angioedema with urticaria is the same as urticaria

alone; if angioedema alone, think hereditary or acquired C1 esterase

inhibitor deficiency

■Skin Biopsy

➣Usually not necessary

➣Helpful if urticarial vasculitis is suspected as vascular damage

will be seen

differential diagnosis

■Erythema multiforme – lesions are fixed, frequently targetoid, often

palmar involvement

■Bullous pemphigoid – urticarial plaques eventually become bullous

■Dermatitis herpetiformis – grouped vesicles and excoriations are

characteristic

■Morbilliform drug eruption – confluent erythematous macules and

papules rather than wheals

management

■Acute urticaria/angioedema

➣Assess airway, breathing, circulation

➣Identify and eliminate etiology if possible

➣Sympathomimetics

➣Antihistamines

➣Systemic corticosteroids may be required but onset of action

delayed

■Chronic urticaria/angioedema

➣Identify and eliminate etiology

➣Avoid physical triggers

➣Antihistamines

➣Nontraditional therapies (IVIg, plasmapheresis, PUVA, immuno-

suppressives such as cyclosporine, methotrexate, azathioprine,

or mycophenolate mofetil)

➣Avoid chronic systemic corticosteroids

➣Avoid aspirin/NSAIDs, narcotics, benzoates, and ACE inhibitors

specific therapy

■Traditional H1 antihistamines

➣Chlorpheniramine maleate

➣Diphenhydramine HCl