Description
Represents approximately 15 to 20% of HAE cases. Similar description to Type I, but C1-inhibitor does not function properly.
Does not respond to antihistamines and corticosteroids.
Common Symptoms
Swelling can occur in the extremities, abdomen, throat and other organs. Swelling of the airway can be fatal. Abdominal swelling usually involves pain, vomiting and diarrhea. Symptoms usually appear early in life, most often by age 13 and may increase in severity after puberty. Episodes may be spontaneous or triggered by physical trauma or emotional stress.
Compliment System
C1-inhibitor level may be normal or elevated, but it is dysfunctional. C1, C3 and C1q are normal, but C4 is almost always low.
Possible Treatment*
Anabolic steroids (also known as androgens) such as danazol, oxandrolone and stanozolol have, historically, been the most commonly prescribed preventive HAE therapies. While anabolic steroids have been shown to be useful, they are not well-tolerated by many women, directly linked to liver toxicity and can cause an increase in cholesterol levels. In addition, these drugs should not be used to treat children, some of whom, tragically, are severely affected and suffer frequent attacks. Research indicates that patients treated with anabolic steroids can experience breakthrough laryngeal or abdominal attacks that require hospitalization. Five new treatments are now FDA-approved for treating HAE, including two C1-inhibitor products, a kallikrein inhibitor, and a bradykinin receptor antagonist. Patients and their physicians now have options for developing a non-steroidal HAE treatment plan tailored to meet each patient's unique needs.
CinryzeTM brand of C1-inhibitor has been FDA-approved for preventing HAE attacks. CinryzeTM is delivered intravenously and is approved for home infusion.
Berinert® brand of C1-inhibitor has been FDA-approved for treating acute abdominal, facial or laryngeal HAE attacks. Berinert® is delivered intravenously and is approved for on-demand treatment through self-administration.
Kalbitor® brand of plasma kallikrein inhibitor has been FDA-approved to treat acute HAE attacks in patients 12 years of age and older. Kalbitor® is delivered through subcutaneous injections.
Firazyr® brand of bradykinin receptor antagonist has been FDA-approved for treating acute HAE attacks in patients 18 years and older. Firazyr® is delivered by subcutaneous injection and is approved for self-administration.
Ruconest® brand of C1-inhibitor [recombinant] has been FDA-approved for treating acute HAE attacks in adults and adolescents. RUCONEST is delivered intravenously and is approved for self-administration.
*Patients with the slightest hint of throat swelling should seek immediate treatment to ensure that their airway is not compromised. The medical literature and practitioner experience confirms that corticosteriods (Prednisone), antihistamines, and epinephrine are not effective in treating angioedema created by C1-inhibitor deficiency. However, a recent study noted success using inhaled epinephrine to prevent complete airway closure. NOTES: The presence of urticaria associated with angioedema usually suggests a diagnosis other than HAE or AAE.