Cold urticaria is one type of chronic inducible urticaria that is relatively uncommon. Exposure to cold air, water, or objects cause the development of urticarial weals.
About 0.05% of the population develops cold-induced urticaria over time. Though often diagnosed in people of young and middle-age, it may also manifest in children and the elderly. It is twice as common in females as in males.
Cold urticaria is a condition that arises as a result of exposure to low temperatures. The mechanism by which the cold stimulus induces the activation of mast cells and the subsequent release of histamine, along with other inflammatory mediators, remains unclear.
Cold urticaria can manifest as either primary (idiopathic) or due to an underlying hematologic or infectious illness. The majority of cases fall under the category of idiopathic, meaning that the cause is unknown.
The symptoms of cold urticaria manifest within a time frame of 2 to 5 minutes following exposure and often persist for a duration of 1 to 2 hours.
Urticaria and angioedema can manifest as either localized, affecting specific areas of the body, or generalized, resulting in a rash that covers the entire body.
Systemic reactions, from mild discomfort to anaphylaxis, have been linked to prolonged exposure to cold, such as when swimming in cold water. Cold-water aquatic activities are dangerous because of the risk of anaphylaxis and secondary drowning.
Patients undergoing surgery under general anesthesia or in cold rooms are also at risk for developing severe reactions.
The diagnosis of cold urticaria may be established with the application of an ice cube to the skin of the forearm for a duration of 1 to 5 minutes. If the patient has cold urticaria, it is expected that a clearly discernible red and swollen rash would develop within a few minutes in the region that has been subjected to the cold-stimulation test.
Associated illnesses may also be identified by doing complete blood count and metabolic testing.
It is important for patients with cold urticaria to take precautions against experiencing a sudden decrease in body temperature. Supervision is required at all times during any aquatic activity (including swimming and surfing).
Patients at risk for anaphylaxis should always have access to adrenaline.
Non-sedating antihistamines at large dosages (up to 40 mg of cetirizine daily, for instance) may be useful. A brief course of oral glucocorticoids may help patients with severe angioedema.
Cautious induction of cold tolerance may be effective (desensitization) by progressively hardening the skin to cold temperatures and then exposing the skin to it frequently, for example, by taking regular cold showers.
Mashael Alanazi, medical student
Maee Barakeh, medical student