Angioedema Angioedema is an allergic reaction caused by certain medications or other allergic materials such as pollen, peanuts and natural rubber latex. This can affect the skin causing abrupt swelling around the eyes and mucous membranes. Angioedema is usually not harmless but has the potential to become life-threatening when it affects the breathing of the individual with swelling of the throat and tongue.
Causes There are various types of angioedema with different causes. In some individuals, certain food can trigger allergic reactions commonly known as a food allergy (allergic angioedema) that can consist of shellfish, peanuts, eggs and milk. When the allergy is caused by certain medications such as those used to treat high blood pressure, this is known as drug-induced angioedema. In addition, the common allergens include pollen and animal dander. Hereditary angioedema is a rare form inherited from the parents and is a lifelong condition. The inherited form is associated with the abnormal function of a protein essential in regulating the immune system. When the cause of the allergy is not known, it is called idiopathic angioedema.
Symptoms The swelling commonly occurs around the eyes, cheeks and lips but can also develop in the hands, feet, tongue and genitals. Several of the individuals affected with angioedema have an itchy rash known as urticaria (hives). The physical signs include thick welts, swelling, redness and pain of the affected area. The swelling of the intestinal tract lining can cause gastrointestinal pain and the severe onset can affect the throat or tongue creating breathing difficulties. Diagnosis The diagnosis may be based on the evaluation of physical examination of the swelling and the medical history to identify the cause of this condition. When the allergy is suspected, the diagnosis may include a skin prick test and a blood analysis. The skin prick test involves introducing a tiny amount of allergen material to observe a reaction. The blood test can identify if the immune system reacts to the allergen.
Treatment If individuals are suspected of an allergic condition, they may be recommended to an allergy specialist. The treatment usually depends on the cause and the type of angioedema affecting the individual. Normally, the swelling may subside on its own within a few days. However, certain medications are available to treat this course and reduce the risk of developing another episode. Antihistamine is the treatment for idiopathic and allergic angioedema, while the drug-induced angioedema may resolve on its own when the medication is terminated or different drugs are administered. The hereditary angioedema cannot be cured but medications can treat the swelling.
Risk Factors This is usually a common condition and the risk of developing it is increased if the individual had hives or angioedema in the past. In addition, they may be prone to develop this condition if a disorder associated with angioedema such as thyroid condition or if a history of angioedema is identified in the family.
References http://www.mayoclinic.org/diseases-conditions/hives-and-angioedema/basics/tests-diagnosis/con-20014815 http://www.nhs.uk/Conditions/Angioedema/Pages/Diagnosis.aspx http://www.dermnetnz.org/topics/angioedema/
