Can a 29-year-old woman’s allergies cause angioedema?

Question

Hello doctor,

I am a 29-year-old woman recently diagnosed with chronic urticaria. I visited an allergist for skin testing due to extreme sensitivity and reactions to various substances. They performed the RAST (radioallergosorbent test) test, which showed class 0 for most allergens, but class 2 for egg white, wheat, and oats, and class 1 for milk and hazelnut.

Can these allergens cause anaphylaxis?
How reliable is the RAST test?
Although I am on an elimination diet, I still experience hives and occasional angioedema. Can angioedema lead to anaphylaxis?

I am extremely concerned about the possibility of my throat closing up, which has made me fearful of eating. I am currently consuming only a few foods daily to minimize my risk.

Please help.

Thank you.

Answer 1

Hello,

Welcome to icliniq.com.

RAST (radioallergosorbent test) is a highly accurate test. If the test is positive for a specific allergen, it shows that you are sensitized to that particular allergen. This means that you may mount an allergic response when you are exposed to that allergen. However, it does not mean that you will necessarily have an allergic reaction to that substance and, nor does it mean that any reactions will be severe.

If the test is negative, it indicates that you do not have the ability to mount an allergic reaction to that allergen, and any symptoms you may be experiencing are likely not due to an allergic reaction to that substance. However, RAST results should be interpreted in conjunction with your clinical history. For example, the presence of an allergy to certain allergens, whether environmental or dietary does not necessarily mean they are responsible for your symptoms, especially if those allergens are not present in your environment or diet. In your case, since the elimination diet has not been effective, this underscores the importance of interpreting RAST test results in conjunction with clinical history. It does not necessarily mean you will have an allergic reaction to the substances tested.

Angioedema is frequently associated with urticaria, as both conditions share similar pathogenesis. However, the presence of angioedema does not always indicate anaphylaxis. Angioedema can be a component of anaphylaxis in individuals who have a severe allergic reaction to an allergen, especially if they have high levels of antibodies circulating in their blood. Since you only have class 1 and 2 level antibodies, it is unlikely that these antigens or allergens would cause anaphylaxis.

Feel free to follow up with any questions.

Thanks you.