part_of part of part of has_disease_location cold urticaria zone of skin acquired cold urticaria Gautier Koscielny ACU Acquired cold urticaria (ACU) represents a form of inducible urticaria that is characterized by the development of wheals, angioedema, or both in response to exposure to cold air, solids, or liquids.1 ACU symptoms are usually limited to areas of the skin that have been exposed to cold. However, extensive cold contact may result in generalized symptoms, such as headache, dyspnea, hypotension, and a loss of consciousness.