Urticaria (from the Latin urtica, nettle Nettle is the common name for between 30-45 species of flowering plants of the genus Urtica in the family Urticaceae, with a cosmopolitan though mainly temperate distribution. They are mostly herbaceous perennial plants, but some are annual and a few are shrubby (whence It. ortica, Sp. ortiga, Pg. urtiga) urere, to burn)[1] (or hives) are a kind of skin rash notable for dark red, raised, itchy bumps. Hives are frequently caused by allergic reactions; however, there are many non-allergic causes. For example, most cases of hives lasting less than six weeks (acute urticaria) are the result of an allergic trigger. Chronic urticaria (hives lasting longer than six weeks) are rarely due to an allergy. The majority of patients with chronic hives have an unknown (idiopathic Idiopathic is an adjective used primarily in medicine meaning arising spontaneously or from an obscure or unknown cause. From Greek ἴδιος, idios + πάθος, pathos (suffering), it means approximately "a disease of its own kind.") cause. Perhaps as many as 30-40% of patients with chronic idiopathic urticaria will, in fact, have an autoimmune cause. Acute viral infection is another common cause of acute urticaria (viral exanthem An exanthem is a widespread rash usually occurring in children. Exanthems can be caused by toxins or drugs, microorganisms, or can result from autoimmune disease). Less common causes of hives include friction, pressure, temperature extremes, exercise, and sunlight.
Wheals (raised areas surrounded by a red base) from urticaria can appear anywhere on the surface of the skin. Whether the trigger is allergic or non-allergic, there is a complex release of inflammatory mediators, including histamine Histamine is a biogenic amine involved in local immune responses as well as regulating physiological function in the gut and acting as a neurotransmitter. Histamine triggers the inflammatory response. As part of an immune response to foreign pathogens, histamine is produced by basophils and by mast cells found in nearby connective tissues from cutaneous mast cells A mast cell is a resident cell of several types of tissues and contains many granules rich in histamine and heparin. Although best known for their role in allergy and anaphylaxis, mast cells play an important protective role as well, being intimately involved in wound healing and defense against pathogens, resulting in fluid leakage from superficial blood vessels. Wheals may be pinpoint in size, or several inches in diameter. Angioedema Angioedema is the rapid swelling (edema) of the dermis, subcutaneous tissue, mucosa and submucosal tissues. It is very similar to urticaria, but urticaria, commonly known as hives, occurs in the upper dermis is a related condition (also from allergic and non-allergic causes), though fluid leakage is from much deeper blood vessels. Individual hives that are painful, last >24 hours, or leave a bruise as they heal are more likely to be a more serious condition called urticaria pigmentosa Urticaria pigmentosa (also known as "Generalized eruption of cutaneous mastocytosis ":616 ) is the most common form of cutaneous mastocytosis. It is a rare disease caused by excessive numbers of mast cells in the skin that produce hives or lesions on the skin when irritated. Hives caused by stroking the skin (often linear in appearance) are due to a benign condition called dermatographism Dermatographic urticaria is a skin disorder seen in 4–5% of the population and is one of the most common types of urticaria, in which the skin becomes raised and inflamed when stroked or rubbed with a dull object.
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El Correo de Andalucia
Los sintomas de estas suelen ser los mismos que el de todas las alergias ( urticaria , problemas gastrointestinales o respiratorios) y la solucion, ...
