A challenging case of bradykinin-mediated angioedema with airway obstruction: management and therapeutic strategies

Abstract

Angioedema is a potentially life-threatening condition that can have an allergic origin, usually mediated by histamine or a non-allergic origin, mediated by bradykinin. The distinction between these origins may present a clinical challenge at first approach, especially in cases that appear as an emergency and the outcome is time dependent. The authors describe a rare case of bradykinin angioedema associated with airway obstruction and discuss the right approach and therapeutic options. A 46-year-old patient under ACE inhibitor, renin-angiotensin-aldosterone blocker and beta blocker presented with difficulty swallowing, shortness of breath and angioedema, associated with inspiratory stridor, incapacity of talking, plantar pruritus and vomits minutes after ingestion of shrimp. The symptoms did not respond to epinephrine, anti-histamines or steroids. The airway quickly became an emergency and the authors discuss the importance of airway obstruction management and having a multidisciplinary well-defined plan of approach with backup plans. Exuberant angioedema persisted leading to the suspicion of drug induced angioedema. Treatment with tranexamic acid 1g 6/6h and icatibant 30 mg 6/6h (3 doses) was started with resolution. In these cases, the rapid institution of the right pharmacological line will relate significantly to a better outcome. It is particularly important because, as their underlying physiopathologic mechanism differ, bradykinin mediated angioedema does not respond to drugs that histamine mediated angioedema does, like corticosteroids and antihistaminic. In severe and life-threatening cases icatibant and tranexamic acid have proven to be an effective therapy.

Keywords: airway obstruction; angioedema; bradykinin; histamine; icatibant; tranexamic acid.

Fig. 1

Mechanism of bradykinin-mediated angioedema.