Angioneurotic edema is an inflammatory, vascular reaction with urticaria and edema of the skin, mucous membranes, or viscera.

This reaction can be due to sensitivity to certain foods (often nuts, shellfish, or eggs), molds, drugs, insect bites or stings, and allergy (desensitization) shots. There is a form called hereditary angioedema, which usually involves lesions in the gastrointestinal (GI) and respiratory tracts, and is caused by a deficiency of complement. A positive family history correlates with this disorder.

Manifestations of the two types of angioneurotic edema are as follows:

• Angioedema: There is localized edema of the deep dermis and subcutaneous tissue of the skin with giant wheals. There may be non-pitting edema of the eyelids, mucous membrane, genitalia, or lips. There is no itching with the swelling, but rather a tingling and burning sensation. If there is edema of the upper airways, then respiratory distress is a possibility, and the patient's breathing may be mistaken for asthma.

• Hereditary angioedema: Gastrointestinal symptoms of nausea, vomiting, intestinal colic, and possible intestinal obstruction are presented. Angioedema of the larynx could cause fatal airway obstruction.

Measures to identify the two types of conditions are as follows:

• Angioedema: For this type, a search for the cause is required. A patient history regarding foods, drugs and environment can help determine allergic agents. Routine tests (complete blood count [CBC], urinalysis, erythrocyte sedimentation rate [ESR] and chest x-ray) will help rule out infections.

• Hereditary angioedema: For this type, measurement of complement may show a decrease.

Measures to treat the two types of conditions are as follows:

• Angioedema: The goal is to limit what triggers the reaction, relieve symptoms, and establish desensitization. Antihistamines can ease the symptoms, but for severe reactions, a glucocorticoid may be needed. If laryngeal symptoms become evident, then epinephrine will be used first along with an antihistamine administered intravenously (IV) to prevent airway obstruction.

• Hereditary angioedema: If short-term prophylactic therapy is needed for minor surgery procedures, then fresh frozen plasma is given to supply complement. Long-term treatment may require oral androgen to raise the deficiency level to normal.

Airway obstruction in either type of condition could result in the need for a tracheostomy or endotracheal intubation.

• None.

Notes

• The rating criteria for cardiovascular conditions underwent full-scale revision effective on November 14, 2021 and January 12, 1999.  A regulatory change was effective August 13, 1998, updated criteria for cold injury residuals under 38 CFR 4.104, DC 7122.  The changes are not considered liberalizing and should not be used as the basis for reduction unless the disability has actually improved.