Mimics of Angioedema
Monday, March 7, 2016
South Exhibit Hall H (Convention Center)
Jacqueline Hirsh, Christina C. Price, MD
Rationale: Allergy & Immunology specialists are often consulted for the clinical question, “Does this patient have angioedema?”  Our goal was to identify mimics of angioedema, which should be considered when confronted with a patient who presents with possible angioedema.

Methods: Cases of presumed angioedema in a large, urban teaching hospital were reviewed. Atypical clinical and laboratory features were identified. 

Results: Two patients with presentations concerning for angioedema but unrevealing work-ups were identified. Patient 1, a 49-year-old man, presented in 2013 with laryngeal and epiglottal edema in the absence of urticaria or tongue swelling, but with airway compromise requiring intubation. He had several similar subsequent presentations. C1 esterase and C4 levels were normal. He was ultimately found to have SVC syndrome with subclavian stenosis, which is the likely etiology of his presentation. Patient 2, a 65-year-old man, presented in 2014 with dysarthric speech and tongue swelling. He, too, had normal C1 esterase and C4 levels. He was ultimately diagnosed with myasthenia gravis to which his angioedema-like picture was attributed. Both of these patients’ angioedema-like presentations were initially attributed to ACE-inhibitor exposure, but they were subsequently found to have more plausible etiologies mimicking angioedema. 

Conclusions: Although angioedema is a common diagnosis made by Allergy & Immunology specialists, many mimics exist. When hereditary angioedema is ruled out, as it was in our two patients, the question of secondary etiology versus angioedema-mimic arises. In the two patients reviewed, ACE-inhibitor-induced angioedema was the initial diagnosis until their clinical syndromes revealed themselves as mimics of angioedema.