Symptom history. Allergic angioedema often has a rapid onset and resolution, whereas hereditary and acquired subtypes appear more gradually.2 While the presence of urticaria distinguishes a histaminergic reaction, both histaminergic and nonhistaminergic angioedema may manifest without this symptom.
In our patient, the timeline of gradual symptom manifestation and the physical exam findings, as well as the patient’s age, tobacco history, and recent initiation of an ACE inhibitor, made acquired angioedema a more likely etiology.
Treatment for ACE inhibitor–induced angioedema, in addition to airway support, entails drug discontinuation. This typically leads to symptom resolution within 24 to 48 hours.2 Treatment with corticosteroids, antihistamines, and epinephrine is usually ineffective. Switching to an alternative ACE inhibitor is not recommended, as other members of the class carry the same risk. Instead, angiotensin receptor blockers (ARBs) are an appropriate substitute, as the incidence of cross-reactivity in ACE inhibitor–intolerant patients is estimated to be 10% or less,5 and the risk for recurrence has been shown to be no different than with placebo.3,4
Our patient was transitioned to losartan 25 mg/d without recurrence of his symptoms and with continued blood pressure control (125/60 mm Hg).
THE TAKEAWAY
Angioedema is a common condition. While many medications are associated with histaminergic angioedema, ACE inhibitors are a common cause of the acquired subtype of nonhistaminergic angioedema. Commonly affected sites include the lips, tongue, and face; however, this diagnosis is not dependent on location and may manifest at other sites, as seen in this case. Treatment involves medication discontinuation. When switching the patient’s medication, other members of the ACE inhibitor class should be avoided. ARBs are an appropriate alternative without increased risk for recurrence.
CORRESPONDENCE
Katherine Montag Schafer, University of Minnesota— Department of Family Medicine and Community Health, 1414 Maryland Avenue E, St Paul, MN 55106; monta080@umn.edu