Kam L. Hon*, Alexander K.C. Leung, Wing G.G. Ng and Steven K. Loo Pages 27 - 37 ( 11 )
Background: Up to 1% of the general population in the USA and Europe suffer from chronic urticaria (CU) at some point in their lifetime. CU has an adverse effect on the quality of life.
Objective: This study aims to provide an update on the epidemiology, pathogenesis, clinical manifestations, diagnosis, aggravating factors, complications, treatment and prognosis of CU.
Methods: The search strategy included meta-analyses, randomized controlled trials, clinical trials, reviews and pertinent references. Patents were searched using the key term "chronic urticaria" at the following links: www.google.com/patents, www.uspto.gov, and www.freepatentsonline.com.
Results: CU is a clinical diagnosis, based on the episodic appearance of characteristic urticarial lesions that wax and wane rapidly, with or without angioedema, on most days of the week, for a period of six weeks or longer. Triggers such as medications, physical stimuli, and stress can be identified in 10 to 20% of cases. C-reactive protein/erythrocyte sedimentation rate, and complete blood cell count with differential are the screening tests that may be used to rule out an underlying disorder. The mainstay of therapy is reassurance, patient education, avoidance of known triggers, and pharmacotherapy. Secondgeneration H1 antihistamines are the drugs of choice for initial therapy because of their safety and efficacy profile. If satisfactory improvement does not occur after 2 to 4 weeks or earlier if the symptoms are intolerable, the dose of second-generation H1 antihistamines can be increased up to fourfold the manufacturer’s recommended dose (all be it off license). If satisfactory improvement does not occur after 2 to 4 weeks or earlier if the symptoms are intolerable after the fourfold increase in the dosage of second-generation H1 antihistamines, omalizumab should be added. If satisfactory improvement does not occur after 6 months or earlier if the symptoms are intolerable after omalizumab has been added, treatment with cyclosporine and second-generation H1 antihistamines is recommended. Short-term use of systemic corticosteroids may be considered for acute exacerbation of CU and in refractory cases. Recent patents for the management of chronic urticaria are also discussed. Complications of CU may include skin excoriations, adverse effect on quality of life, anxiety, depression, and considerable humanistic and economic impacts. On average, the duration of CU is around two to five years. Disease severity has an association with disease duration.
Conclusion: CU is idiopathic in the majority of cases. On average, the duration of CU is around two to five years. Treatment is primarily symptomatic with second generation antihistamines being the first line. Omalizumab has been a remarkable advancement in the management of CU and improves the quality of life beyond symptom control.
Angioedema, antihistamines, hives, immunomodulators, pruritus, vasculitis, wheals.
Department of Paediatrics, The Chinese University of Hong Kong, Shatin, Department of Pediatrics, The University of Calgary, Alberta Children's Hospital, Calgary, Alberta, Department of Pediatrics, The University of Calgary, Alberta Children's Hospital, Calgary, Alberta, The Institute of Integrative Medicine, The Chinese University of Hong Kong, Shatin