Definition
Hives is also called “urticaria” or colloquially hives fever. It is a typical, symptomatic clinical picture of the skin, which can be caused by a variety of triggers. The mechanism by which the superficial symptoms of the skin develop is comparable to an allergic reaction, but an allergy is the actual trigger in only about 10% of cases. The disease can occur suddenly or take a chronic course, it can also appear once or recur repeatedly.
Causes
The causes of hives are numerous. Hives as a clinical picture represents a series of symptoms of the skin that can occur due to various stimuli. These stimuli can be triggered autoimmunologically, physically, chemically, infectiously or otherwise.
Often there is a hypersensitivity to supplied substances. These can be certain foods, drugs, drinks, ointments or similar. The skin reacts with allergy-like symptoms to the supposedly harmful substance.
Another cause can be so-called pseudoallergies, such as sweat allergy. The physical causes of hives can be pressure, friction, heat or cold. In rare cases, sunlight or water can also lead to skin symptoms.
Hormonal disorders of the body can also trigger the symptoms. Changes in the skin can be influenced by the nervous system and hormones like adrenaline. If these hormones are misregulated, hives can be triggered.
For example, thyroid inflammation of the autoimmune type can cause such misregulations. Rare autoimmune processes and metabolic disorders can also trigger chronic hives. In autoimmune reactions, the immune system triggers the symptoms because it falsely recognizes endogenous substances as harmful and fights them.
In very rare cases, a metabolic disorder is caused by the breakdown of the hormone histamine. This hormone is mainly released during allergic reactions. If it cannot be broken down properly, the body erroneously develops strong allergic reactions.
Infectious causes of hives are also possible. The causes are pathogens such as bacteria, viruses or fungi, which affect the skin as an accompanying symptom of the infection. The main infection usually takes place in the intestine, but causes hives as an accompanying symptom. If no cause for the hives is identified, which is true in a large proportion of cases, it is called “idiopathic” hives.
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