What are hereditary and acquired C1 inhibitor deficiency?
Hereditary and acquired C1 inhibitor deficiency are also known as hereditary and acquired angioedema. Angioedema is swelling of your face, lips, tongue, and throat that is usually caused by an allergic reaction. But angioedema can also be caused by a certain problem with your immune system.
Hereditary angioedema (also called hereditary C1 inhibitor deficiency) is an immune system problem you're born with
Acquired angioedema (also called acquired C1 inhibitor deficiency) is an immune system problem caused by another illness or condition
Hereditary and acquired angioedema are like angioedema caused by an allergic reaction, but they don't itch and you don't get hives (red, itchy, raised patches on the skin).
Your lips, tongue, and throat may swell, which can cause trouble breathing
You may feel sick to your stomach and throw up
Doctors can use medicines to treat and prevent the swelling
DR P. MARAZZI/SCIENCE PHOTO LIBRARY
What causes hereditary or acquired angioedema?
Hereditary angioedema is genetic (a trait inherited from a parent). The condition is present at birth, but symptoms usually start when you’re a child or teenager.
Acquired angioedema can develop after you get certain cancers or autoimmune diseases (a disease that causes your body's immune system to attack its own tissues). Symptoms usually start later in life.
What can trigger an attack of angioedema?
In both hereditary and acquired angioedema, swelling may be triggered by:
Minor injury
Infection
Certain foods
Pregnancy
Cold
Stress
What are the symptoms of hereditary and acquired angioedema?
Symptoms can include painful swelling in your:
Face
Lips
Tongue
Hands
Feet
Genitals
Lining of your mouth, throat, airways, and digestive tract
Other symptoms include:
Feeling sick to your stomach
Throwing up
Cramps
Swelling in the voice box, throat, or tongue can cause breathing problems.
This photo shows swelling of the lips in a person with hereditary angioedema.
By permission of the publisher. From Joe E, Soter N. In Current Dermatologic Diagnosis and Treatment, edited by I Freedberg, IM Freedberg, and MR Sanchez. Philadelphia, Current Medicine, 2001.
This person has a swollen tongue due to angioedema.
SCIENCE PHOTO LIBRARY
This person has swollen lips due to angioedema.
DR P. MARAZZI/SCIENCE PHOTO LIBRARY
This photo shows swelling of the lips in a person with hereditary angioedema.
By permission of the publisher. From Joe E, Soter N. In Current Dermatologic Diagnosis and Treatment, edited by I Freedberg, IM Freedberg, and MR Sanchez. Philadelphia, Current Medicine, 2001.
This person has a swollen tongue due to angioedema.
SCIENCE PHOTO LIBRARY
This person has swollen lips due to angioedema.
DR P. MARAZZI/SCIENCE PHOTO LIBRARY
How can doctors tell if I have hereditary or acquired angioedema?
Doctors suspect hereditary or acquired angioedema if you have swelling but no hives. To know for sure, they'll do:
Blood tests
How do doctors treat hereditary and acquired angioedema?
Doctors treat you with:
Medicine that helps your immune system
Doctors may also give you medicines to prevent swelling, particularly before known triggers.
Blocked airway treatment
If your airway swells and you have problems breathing, doctors will need to open your airway. To do this, they may:
Give you a shot to lessen swelling
Put in a breathing tube through your nose or mouth
If there is too much swelling around the nose and mouth, put in a breathing tube by cutting into the skin over your windpipe
