Modern approaches to the diagnosis and treatment of cold contact urticaria.

Cold contact urticaria (CCU) is a common subtype of physical urticaria characterized by itchy wheals and/or angioedema due to skin mast cell activation and the release of proinflammatory mediators after cold exposure. The underlying causes are largely unknown. When CCU is suspected, cold stimulation tests and threshold testing should be done to confirm the diagnosis and to determine the severity and course of CCU, respectively. Avoidance of critical cold exposure should be recommended but is often impossible, especially for severely affected patients with high temperature and low exposure time thresholds. Symptomatic treatment of choice is the use of modern, nonsedating antihistamines. Patients should be informed that complete protection from CCU symptom development may require increased doses of antihistamines. Standardizing cold provocation tests and further characterization of the natural course of CCU and its variants may lead to a better understanding of the disease-driving mechanisms.