Understanding Angioedema: What You Need to Know

Angioedema is swelling that can involve subcutaneous or submucous layers of tissue. It is usually non-pitting in nature and can affect the lips, oral cavity, larynx, extremities, and even genital organs. Angioedema affecting the larynx could be life-threatening if not treated promptly, as it can cause difficulty in breathing. Angioedema is usually caused by an allergic reaction to an antigen, except in some forms of angioedema.

Types of Angioedema:

1. Acute Allergic Angioedema:

   • Occurs after exposure to an antigen (allergen). It could be due to contact with grass, food, a cosmetic substance, some medicines, or an insect bite. It is acute in onset, happening quickly within minutes or one to two hours.

2. Non-Allergic Drug-Induced:

   • This type of angioedema has an insidious onset, as it does not occur immediately after the consumption of medicine but rather a few days to a few weeks after starting the medication. The most common drugs causing this type of angioedema are ACE inhibitors and ARBs, which present with complaints of dry cough. Other medicines include Ibuprofen and naproxen.

3. Idiopathic Angioedema:

   • Occurs without a known cause and can be located over the face, trunk, or extremities.

4. Hereditary Angioedema (HAE):

   • An inherited condition affecting 1 in 50,000 people. It is usually associated with C1-esterase inhibitors in the blood.

5. Acquired C1 Inhibitor Deficiency:

   • A very rare form of angioedema characterized by recurrent episodes. It is diagnosed by low levels of C1 inhibitor proteins along with low complement (C4) levels in the blood.

6. Vibratory Angioedema:

   • Can occur after exposure to high vibration, such as working with an electric hammer, drilling machines, heavy massage, or bike riding.

Management:

The treatment of angioedema varies based on the severity of symptoms. Milder forms can be resolved with antihistamines and corticosteroids, but severe cases may require epinephrine.

Case Presentation:

An 8-year-old boy presented with severe swelling of the lower lip for two days. He was stung by a honey bee on his lower lip while playing around his house, where there was a bee hive.

Image 1. Showing maeked non pitting edema over lower lip followed by honey bee stung.

Examination: He was conscious, alert, and afebrile. General physical examination was normal, and vitals were also normal. There was severe non-pitting edema over his lower lip. He was managed with an intravenous injection of Hydrocortisone 100 mg and oral Hydroxyzine, responding well within 48 hours.