A 44-year-old woman comes to the emergency department after waking up with facial swelling and with difficulties speaking and swallowing. She states that she does not have allergies or recently had insect bites. She has a 4-year history of hypertension and type 2 diabetes mellitus controlled with medication. Her pulse is 110/min, respirations are 20/min, and blood pressure is 140/90 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 97%. On physical examination, she appears uncomfortable, with notable swelling of the lips and tongue. The remainder of the examination shows no abnormalities. Serum C4 levels are within normal limits. Which of the following is the most likely mechanism responsible for this patient's symptoms?

Question

Quizplus · Accepted Answer

Eductional Objective: Angioedema is a rare and serious adverse effect of ACE inhibitor therapy.  ACE inhibition increases bradykinin levels, which increase vascular permeability and lead to angioedema.  Symptoms include tongue, lips, or eyelid swelling and, less frequently, laryngeal edema and difficulty breathing.  ACE inhibitors should be discontinued in affected patients.

A 44-Year-Old Woman Comes to the Emergency Department After Waking