Related Terms: angioneutrotic edema, chronic recurrent angioedema, idiopathic angioedema, hereditary angioedema, oedema, allergic reactions, AAE, HAE, hereditary angioneutrotic edema, swelling, allergic angioedema, hives, urticaria, laryngoedema, anaphylaxis, chronic recurrent angioedema, idiopathic angioedema, hereditary angioedema, hereditary angioedema I, hereditary angioedema II, urticaria
Inflammatory condition or response that is characterized by localized swelling (welts) under the surface of the skin, the mucous membranes or an internal organ. Often associated with urticaria, except that the swelling (edema) is below the surface of the skin rather than on top. The swelling can be life threatening as if often occurs in the throat causing airway obstruction thus preventing respiration.
Angioedema and urticaria are varying manifestation of the same pathaoloagical process. Both are described as a post capillary inflammation that results in fluid leakage and edema. The differamce is that angioedema involves vessels in the layers of the indodermal regions whereas uticaria is localized superficial to the dermis. (2)
There are three classifications of angioedema.
Allergic - Also referred to as Chronic Recurrent, this is a response to an allergen such as a food groups (often nuts, certain seafoods), medicines (aspirin being the most common), reaction to latex , pet dander, insect bites (bees, yellow jackets), pollen and can even be triggered by emotional stress. The bodies response meechanism to an allergen is called anaphylaxis. The most common body systems involved with this response are the cutaneous dermal organ (skin), respiratory, cariovascular and gastrointestinal systems.
Unknown etiology - Also referred to as idiopathic angioedema. This is perhaps the most frequent class and can be extremely frustrating as the cause or source of the edema is unknown. Individuals experiencing this form may be referred to an immunologist.
Hereditary - This is the rarest form of angioedema and often runs in families which indicates a possible genetic cause. Individuals with this form exhibit a deficiency of the C1 esterase inhibitor blood protein. Hereditary angioedema may be diagnosed through hematologic workup and has two classifications. Type one, which is the most common is called Hereditary Angioedema I. This type is the result of abnormally low levels of certain complex proteins in the blood (C1 esterase inhibitors) known as complements. They help regulate various body functions (flow of body fluids in and out of cells).
Hereditary Angioedema Type II is a rarer form of the disorder. This type occurs as the result of the production of abnormal complement proteins. (1)
Localized swelling or edema involving the face, lips, or eyes, or tongue; the sudden devlopment of welts, which may be red, itchy or painful; problems with breathing (due to neck or throat edema) and possible abdominal cramping,, which may cause nausea or vomiting.
The edema experienced in angioedema is referred to as localized non-pitting edema .
Other symptoms may include dizziness, nasal congestion, syncope, diarrhea, swollen conjunctiva. All symptoms may occur within five to thirty minutes of exposure to or ingestion of a given allergen.
The diagnosis on angioedema is generally done of the basis of the appearance of the skin and observation of the expression of symptoms. Allergen testing may also be done to determine causative factors.
The response results in the release of histamines, serotonin and kinis with the result that vascular leakage occurs in the dermis and subcutis.
In an acute episode af angioedema, the most serious complication may be laryngoedema, which is the sudden constriction or closure of the larynx. Should this occur, immediate action must be taken to clear the breathing passageway. Other complications that could affect breathing are bronchospams, and swelling of the tongue.
The treatment involved depends on the classification of angioedema. In acute episode, it is imperative that the airway be kept clear. Medications used include steroids, H1 and H2 blockers, epinephrine and antihistimines. Other medications may include Doxepin, Terbutaline, Colchicine, and Danazol.
Hereditary angioedema patients are given aminocaproic acid for maintenance replacement of C1INH to prevent attacks.
For the edema associated with angioedema, decongestive therapy may be prescribed
Patient expectations are excellent, especially upon immediate attention and treatment of episodes. The focus on long term prognosis rests in identifying the causative factors and avoiding them.
For additional Information:(c) Pat O'Connor - Lymphedema People
Urticaria and Angioedema
What is urticaria?
Urticaria, also known as hives, is an outbreak of swollen, pale red bumps or patches (wheals) on the skin that appear suddenly as a result of the body's adverse reaction to certain allergens or for unknown reasons. Hives usually cause itching but may also burn or sting. They can appear anywhere on the body including the face, lips, tongue, throat or ears.
Hives vary in size (from a pencil eraser to a dinner plate) and may join together to form larger areas known as plaques. They can last for hours or up to 3 to 4 days before fading.
What is angioedema?
Angioedema is tissue swelling similar to urticaria, but the swelling occurs beneath the skin instead of on the surface. Angioedema is characterized by deep swelling around the eyes and lips and sometimes of the genitals, hands and feet. Angioedema generally lasts longer than urticaria, but the swelling usually goes away in less than 24 hours.
Occasionally, severe, prolonged tissue swelling can be disfiguring. Rarely, angioedema of the throat, tongue or the lungs can block the airways, causing difficulty breathing and become life-threatening.
What causes hives and angioedema?
Hives and angioedema form when blood plasma leaks out of small blood vessels in the skin because a chemical called histamine is released. Histamine is released from mast cells along the blood vessels in the skin. Allergic reactions, chemicals in foods, insect stings, sunlight exposure or medications can cause histamine release. Sometimes it's impossible to find out why hives have formed.
Types of urticaria and angioedema
Acute Urticaria: hives lasting less than six weeks. The most common causes are foods, medications, latex or infections. Insect bites and internal disease may also be responsible. The most common foods that cause hives are nuts, chocolate, fish, tomatoes, eggs, fresh berries and milk. Fresh foods cause hives more often than cooked foods. Food additives and preservatives may also be the cause. Medications that can cause hives and angioedema include aspirin and other nonsteroidal anti-inflammatory medications such as ibuprofen, high blood pressure medications (ACE inhibitors) or pain-killers such as codeine.
Chronic Urticaria and Angioedema: hives lasting more than six weeks. The cause of this type of hives is usually more difficult to identify than that of acute urticaria. In patients with chronic urticaria, the cause is found in only a small number of patients and is unknown for more than 80 percent of patients. Chronic urticaria and angioedema can effect other internal organs (such as the lungs and gastrointestinal tract), and can cause symptoms of shortness of breath, vomiting, and diarrhea.
Physical Urticaria: hives caused by direct physical stimulation of the skin such as cold, heat, sun exposure, vibration, pressure, sweating, exercise and others. The hives usually occur at the site of direct stimulation and rarely, appear on other skin areas. Most of the hives appear within one hour after exposure.
Dermatographism: hives that form after firmly stroking or scratching the skin. These hives can also occur along with other forms of urticaria. This type of hives is considered a normal variant of the skin.
How are hives and angioedema diagnosed?
Your doctor will need to ask many questions in an attempt to find the possible cause. Since there are no specific tests for hives or the associated swelling of angioedema, testing will depend on your medical history and a thorough examination by your dermatologist. Skin tests may be performed to determine the substance that you are allergic to. Routine blood tests are done to determine if a systemic illness is present.
How are hives and angioedema treated?
The best treatment for hives and associated swelling is to identify and remove the trigger. This is not an easy task. Antihistamines are usually prescribed by your dermatologist to provide relief from symptoms. Antihistamines work best if taken on a regular schedule to prevent hives from forming.
Chronic hives may be treated with antihistamines or combination medications. When antihistamines do not provide relief, oral corticosteroids may be prescribed. For severe hive or angioedema outbreaks, an injection of epinephrine (adrenaline) or a cortisone medication may be needed.
How can hives be managed?
While you’re waiting for the hives and swelling to disappear, here are some tips:
Avoid hot water; use lukewarm water instead
Use gentle, mild soap
Apply cool compresses or wet cloths to the affected areas
Try to work and sleep in a cool room
Wear loose-fitting lightweight clothes
When should I call the doctor?
If hives or angioedema occur with any of the following symptoms, please contact your doctor right away:
Tightness in the chest
Swelling of the tongue, lips or face
Also contact your doctor if your hives have lasted longer than a few days, if they continue to recur over a month or longer, or if you have symptoms of angioedema or anaphylaxis
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Angioedema - eMedicineUnusual Presentations of Hereditary Angioedema and Acquired Angioedema