Systemic diseases can cause angioedema and urticaria. This is generally related to auto-antibody formation, where our own antibodies attack our receptors attached to white blood cells. Anti-Thyroid antibodies that affect the thyroid can also trigger a release of mediators from our white blood cells.
Liver disease, additional chronic diseases and cancers are related to angioedema and urticaria. Remember though, most cases of urticaria and angioedema are idiopathic and will usually last for a short time. If the urticaria appears for more than six months, it is labeled chronic urticaria.
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