Chronic Spontaneous Urticaria: Anti-IgE and Beyond

Overview / Definition Chronic spontaneous urticaria (CSU) is defined as the occurrence of wheals and/or angioedema for more than six weeks without an identifiable external trigger. This condition is often idiopathic, though it may arise from underlying autoimmune mechanisms. Epidemiology CSU affects approximately 0.5% to 1% of the population, with a higher prevalence in women compared to men. The condition can develop at any age, but it most commonly presents in young adults. Age of onset: Typically between 20-40 years. Gender: Female to male ratio is approximately 2:1. Duration: Symptoms can persist for months to years. Pathophysiology / Mechanism The precise mechanism underlying CSU remains complex and multifactorial. The pathophysiology involves: Histamine release: Mast cells in the skin release histamine and other mediators, leading to vasodilation and increased vascular permeability. Autoimmunity: In some patients, there are autoantibodies against the high-affinity IgE receptor (FcεRI) or IgE itself. Inflammatory mediators: Other cells such as eosinophils and basophils may also play a role in the inflammatory response. Clinical Presentation Patients with CSU typically present with: Wheals: Raised, itchy welts that can vary in size and shape. Angioedema: Swelling of deeper layers of the skin, often affecting the face, lips, or extremities. Pruritus: Intense itching is often associated with wheals and angioedema. Symptoms may worsen with stress, heat, or exercise. Diagnosis / Workup The diagnosis of CSU is primarily clinical. A thorough history and physical examination are essential. Key components of the workup include: History: Duration, frequency, and triggers of symptoms. Physical exam: Identification of wheals and angioedema. Laboratory tests: Often not necessary, but can include: Complete blood count (CBC) Thyroid function tests Serum IgE levels Treatment / Management The management of CSU aims to control symptoms and improve the quality of life. Treatment