TY - CHAP M1 - Book, Section TI - Urticaria & Angioedema A1 - Hay, Jr, William W. A1 - Levin, Myron J. A1 - Deterding, Robin R. A1 - Abzug, Mark J. PY - 2017 T2 - Quick Medical Diagnosis & Treatment Pediatrics AB - Common dermatologic conditions that occur at some time in up to 25% of the populationUrticarial lesions are arbitrarily designated asAcute: lasting less than 6 weeksChronic: lasting more than 6 weeksCause of acute urticaria can be identified in about half of patients and includesInfectious allergens agents, including streptococci, mycoplasmas, hepatitis B virus, and Epstein-Barr virusAllergies to foods, aeroallergens, latex, drugs, or insect venomsAcute urticaria can be induced by opiate analgesics, polymyxin B, tubocurarine, and radiocontrast media via direct mast cell activationUrticaria and angioedema can also occur following ingestion of aspirin or nonsteroidal anti-inflammatory agentsUrticaria or angioedema can occur after the administration of blood products or immunoglobulin from immune complex formation with complement activation, vascular alterations, and triggering of mast cells by anaphylatoxinsInducible (physical) urticariasRepresent a heterogeneous group of disorders in which urticaria or angioedema is triggered by physical stimuli, including pressure, cold, heat, water, or vibrationsDermographism is the most common form of physical urticaria, affecting up to 4% of the population and occurring at skin sites subjected to mechanical stimuliLesions are usually rapid in onset, with resolution within hours; however, symptoms can recur for months to yearsChronic spontaneous urticariaUsually not due to allergies and typically cannot be determinedCan be associated with autoimmunity (such as autoimmune thyroid disease) or the presence of basophil-activating IgG autoantibodies directed at the high-affinity receptor for IgE or at IgE SN - PB - McGraw-Hill Education CY - New York, NY Y2 - 2024/03/29 UR - accesspediatrics.mhmedical.com/content.aspx?aid=1145459416 ER -