Symptoms

The frequency, severity, and location of HAE symptoms can vary widely, even in the same patient.

Many patients experience a "prodrome" one-half hour to several hours before an HAE attack. A prodrome is basically one or more warning signs that an attack is coming, such as:

• A painless, non-itchy rash that may be “S”-shaped; the rash may not necessarily occur in the same location as the attack
• Tingling or a sensation of tightness in an area of skin that later becomes swollen

When HAE Attacks Happen

On average, untreated HAE patients experience greater than 20 attacks per year, each generally lasting between 2 and 5 days.

When an attack occurs, the symptoms typically worsen for the first 24-36 hours, then slowly resolve during the next 36-48 hours. Attacks frequently result in hospitalization, may lead to unneeded abdominal surgery, and can be life-threatening when involving the airway.

Once the symptoms have resolved, most HAE patients are relatively unlikely to experience another HAE attack for approximately a week. Many patients with untreated HAE have a natural attack frequency of every 10 to 14 days.

Subcutaneous Swelling

Most HAE attacks involve swelling of the face, extremities (hands and feet), or genitals. This type of attack affects the subcutaneous tissue, or the tissue just beneath the skin. Although uncomfortable and disfiguring, the swelling is usually painless unless it occurs in a pressure-bearing area or in an area with little subcutaneous tissue.

Facial swelling most often involves the lips, eyelids, or tongue; the swelling is sometimes accompanied by redness that looks like a rash, although it doesn't itch. These attacks, while uncomfortable and disfiguring, are usually painless.

Abdominal Attacks

The abdomen is the second most common site of HAE attacks. Abdominal attacks have been reported in more than 93% of patients and make up almost 50% of all angioedema attacks.

Swelling of the gastrointestinal tract can cause nausea, vomiting, and severe pain, and is rarely accompanied by fever. Abdominal symptoms usually resolve more quickly than other attack locations, and diarrhea may occur as the attack subsides.

An abdominal attack may be hard to distinguish from other abdominal ailments. In fact, many HAE patients undergo unnecessary surgery, particularly before their disease is diagnosed. In one review of 235 HAE patients, 34% had an appendectomy and/or exploratory laparotomy during an attack.

Laryngeal Attacks

Although much less common than the other types of attacks, swelling of the larynx (laryngeal attacks) is the most dangerous, because it can obstruct the airway. Research indicates that in patients with undiagnosed HAE, mortality has been reported to be as high as 40% as a result of a laryngeal attack.

Approximately 50% of all HAE patients experience a laryngeal attack at least once in their lifetime, and some patients have them repeatedly. Laryngeal attacks can occur at any age, but are most common in patients between the ages of 11 and 45. These attacks are especially dangerous in young children, who have small airways.

Less than 5% of laryngeal attacks are linked to an identifiable trigger. Attacks may begin with difficulty swallowing and a change in voice tone. They usually develop over a period of hours, but can occur in as rapidly as 20 minutes. 

This type of attack is an emergency - seek medical treatment immediately. Always carry an HAE wallet card  or a letter from your doctor with you in case you have an attack and are unable to speak.