ACE inhibitor-induced bradykinin-mediated angioedema presenting as small bowel obstruction and life-threatening airway angioedema: a rare dual presentation.

Angiotensin-converting enzyme inhibitors (ACEi) are the leading cause of drug-induced angioedema in the USA, with an incidence of 0.1-0.7%. While ACEi-induced angioedema (ACEi-AE) typically affects the lips, tongue, face and airways, visceral angioedema is rare and usually occurs within 72 hours of starting therapy. However, there have been cases reported after months or years of ACEi use.We present a rare case of an elderly female in her mid-80s on lisinopril for 11 years who developed abdominal pain, nausea and vomiting. She was diagnosed with small bowel obstruction and later developed respiratory distress. Imaging and clinical findings led to the diagnosis of ACEi-AE. Discontinuation of lisinopril and treatment with fresh frozen plasma (FFP) resulted in resolution of symptoms. This case highlights the importance of considering ACEi-induced small bowel angioedema in the differentials for small bowel obstruction, thus preventing unnecessary surgical intervention. We also conclude that FFP is a promising treatment option for ACEi-AE.