As long as the weather is cold or the wind blows, the skin at the joints will be red or white, which is particularly itchy. What's going on?

Tips: The reply is for reference only and cannot replace the clinical diagnosis. Please go to the relevant hospital for final diagnosis:

Cold urticaria

Cold urticaria is a special type of urticaria, which occurs mostly in winter and is an allergic reaction caused by human contact with cold environment. Edema and wheal often occur in the parts immersed in cold water or in contact with cold substances, mostly in the face and hands, but also in other parts, consciously itching, and some have headache, skin flushing, hypotension and other systemic symptoms. In severe cases, shock will occur. In addition, there is a familial cold urticaria, which often occurs in infancy and can be seen as early as 1 week after birth. The patient developed a rash from half an hour to four hours after catching cold, which did not itch. The rash is erythema and wheal, accompanied by fever, cold, joint pain, headache and other systemic symptoms.

Cold urticaria is a kind of urticaria, and its clinical manifestations are mainly itching and wheal in different parts under cold conditions. Skin lesions can be confined to exposed parts or parts that come into contact with cold objects under cold conditions, or they can be systemic, involving oral mucosa, and even manifested as headache, chills, diarrhea and tachycardia. There are many opportunities to contact cold objects in winter, so this disease is easy to occur.

Cold urticaria can be divided into two categories: acquired and familial. Acquired cold urticaria can be divided into primary and secondary. Histamine is the most important inflammatory factor, but prostaglandin and kinin are related to the occurrence of this disease. Histamine releasing factor exists in the blood of patients with spontaneous cold urticaria. The wheal or normal skin of patients with this disease can induce wheal after cold stimulation. Secondary cold urticaria is closely related to some diseases, such as cryoglobulinemia, cold fibrinogen, infectious mononucleosis, rubella, HIV, syphilis, connective tissue disease, bone marrow malignant tumor and so on.