Cold urticaria (essentially meaning cold hives) is a disorder in which large red welts called hives (urticaria) form on the skin after exposure to a cold stimulus. The hives are usually itchy and often the hands and feet will become itchy and swollen as well. Hives vary in size from about in diameter to as big as about or larger. This disorder, or perhaps two disorders with the same clinical manifestations, can be inherited (familial cold urticaria) or acquired (primary acquired cold urticaria). The acquired form is most likely to begin between ages 18 and 25, although it can occur as early as 5 years old in some cases. Life-threatening risks include suffocation resulting from swollen tissue (pharyngeal angioedema) induced by cold foods or beverages, drowning after shock from swimming in cold water, and anaphylactic shock. Types Cold urticaria may be divided into the following types: Primary cold contact urticaria Primary cold contact urticaria is a cutaneous condition characterized by wheals, and occurs in rainy, windy weather, and after swimming in cold water and after contact with cold objects, including ice cubes. Cold urticaria affect %0.5 of the population. Secondary cold contact urticaria Secondary cold contact urticaria is a cutaneous condition characterized by wheals, due to serum abnormalities such as cryoglobulinemia or cryofibrinogenemia are extremely rare, and are then associated with other manifestations such as Raynaud's phenomenon or purpura. Reflex cold urticaria Reflex cold urticaria is a cutaneous condition in which generalized cooling of the body induces widespread welting. Familial cold urticaria Familial cold urticaria (also properly known as familial cold autoinflammatory syndrome, FCAS) is an autosomal dominant condition characterized by rash, conjunctivitis, fever/chills and arthralgias elicited by exposure to cold - sometimes temperatures below . It has been mapped to CIAS1 and is a slightly milder member of the disease family including Muckle–Wells syndrome and NOMID. It is rare and is estimated as having a prevalence of 1 per million people and mainly affects Americans and Europeans. FCAS is one of the cryopyrin-associated periodic syndromes (CAPS) caused by mutations in the CIAS1/NALP3 (aka NLRP3) gene at location 1q44. The effect of FCAS on the quality of life of patients is far reaching. A survey of patients in the United States in 2008 found that "[t]o cope with their underlying disease and to try to avoid symptomatic, painful, flares patients reported limiting their work, school, family, and social activities. Seventy-eight