USMLE Allergy/Immunology Practice Question

Question

A 32 year-old cardiology fellow  on vacation in Mexico suddenly developed significant swelling of his upper lip. Over the next year he continued to have multiple episodes weekly of severe swelling of portions of his face, trunk, and extremities. These were mildly itchy.  Which of the following is not true?

A. This could be caused by a vasculitis, 

B. Foods, drugs, and infections could be common causes

C. A complement deficiency could be causative

E. Most likely no cause will be found

F. Steroids and antihistamines will likely help with symptoms

Answer 1

Note! This is exactly what happened to me many years ago it was terrible!This is chronic idiopathic angioedema. Long list of possible causes including all types of infections, perhaps particularly parasitic infections. Drugs may cause, always think of ACE inhibitors. May be associated with thyroid, liver disease, autoimmune dz, malignancy, small vessel vasculitis, complement deficiencies. This may be lifelong or self-limited or recurrent. In this type the lesions are not particularly red or itchy. In over 90% of cases despite the depth of investigation no cars will be found. There is no effective treatment. Could be secondary to complement deficiency, particularly C1 esterase inhibitor or function, C4, or C1q. These are associated with Coretta Terry or acquired Angeo Adema and these levels vary. Here there is no family history thus if present one would expect decreased level of call the compliment levels mentioned. Danazol and a couple of therapies including complement replacement have been used On rare occasion with sub optimal success in general. Note other forms of idiopathic angioedema may be more red and itchy, including different varieties of complement deficiencies, and these may respond better to typical medication’s.