Angiotensin-Converting Enzyme (ACE) Inhibitor-Induced Angioedema of the Small Bowel: A Diagnostic Dilemma

Background: Angioedema of the tongue, oral mucosa, and pharynx is a highly visible and easily diagnoseable side effect of Angiotensin-converting enzyme inhibitors (ACEI). Angioedema of the small bowel is a rarer, and underrecognized, adverse event that may present as a diagnostic challenge due to its nonspecific symptoms and lack of visibility, and because of a general lack of awareness of it among physicians. Failure to consider ACEI-induced angioedema of the small bowel in differential diagnoses may result in unnecessary interventions and delay of treatment. Methods: We describe the case of a 61-year-old female who was diagnosed with ACEI-induced angioedema of the small intestine after several repeated evaluations. We undertook a literature search to help provide diagnostic, treatment, and management suggestions in patients with ACEI-induced angioedema of the small intestine. Results and Conclusion: In the literature, we found that age, patient demographics, and careful medical reconciliation, paired with diagnostic clues in radiology, can assist in accurate diagnosis. More broadly, family and emergency medicine physicians, surgeons, radiologists, and internists should be aware of this rare side effect caused by this commonly prescribed medication to avert unnecessary medical treatments and procedures.