Urticaria and Angioedema: Acute and Chronic Management

Overview / Definition Urticaria, commonly known as hives, is a skin condition marked by raised, itchy welts (wheals) due to localized swelling from dermal edema. Angioedema involves deeper layers of the skin, leading to swelling in areas such as the face, lips, and extremities. While acute urticaria can resolve within six weeks, chronic urticaria persists for six weeks or longer. Epidemiology Urticaria affects approximately 20% of the population at some point in their lives. Chronic urticaria has a prevalence of about 1% to 3% in the general population. Both conditions can occur at any age, but chronic forms are more prevalent in adults, particularly women. Pathophysiology / Mechanism The pathophysiology of urticaria primarily involves the release of histamine and other inflammatory mediators from mast cells and basophils. This release can be triggered by various factors, including: Allergic reactions (food, medication, insect stings) Physical stimuli (pressure, temperature changes) Infections (viral, bacterial) Autoimmune disorders Stress and anxiety In chronic urticaria, a significant proportion of cases are idiopathic, with an underlying autoimmune mechanism suspected in some instances. Clinical Presentation Patients with urticaria present with: Wheals: Raised, itchy lesions that can vary in size and shape. Pruritus: Intense itching often accompanies wheals. Angioedema: Swelling that often affects the face, lips, tongue, and hands. Acute vs. chronic: Acute urticaria typically lasts less than six weeks, while chronic urticaria persists for six weeks or more. Diagnosis / Workup The diagnosis of urticaria is primarily clinical. A thorough history and physical examination are essential. Key steps include: History: Document the onset, duration, and characteristics of the rash; identify potential triggers. Physical examination: Assess for wheals and angioedema. Laboratory testing: Consider tests for specific triggers (e.g., CBC, IgE levels, thyroid function tests) if c