A CASE OF DIFFICULT TO DIAGNOSE C1INH NORMAL HAE

Abstract

<h3>Introduction</h3> Hereditary Angioedema (HAE) is characterized by recurrent swellings of the face, tongue, oropharynx, extremities, and abdomen. Typically beginning in the second decade of life, these swells often require emergent treatment and may result in intubation. Unchecked production of bradykinin, typically due to low levels of C1 esterase inhibitor (C1INH), results in bradykinin mediated vascular leakage and swelling. Type I and II can be diagnosed by checking C1INH levels and function but C1INH Normal continues to be difficult to diagnose. We present a challenging case detailing the diagnosis and management of probable C1INH normal HAE in a 42-year-old female. <h3>Case Description</h3> A 42-year-old woman with a history of hypothyroidism, GERD, migraine, obesity, and borderline personality disorder, presented to our clinic with a 10-year history of three or more weekly episodes of throat and eyelid angioedema, accompanied by intermittent urticaria. Her controller therapy included montelukast, fexofenadine, cetirizine, zyflo, famotidine, and cromolyn. Despite this regimen, she continued her thrice weekly episodes, so cyclosporine was added without improvement in flare frequency or severity. C1INH level and function, along with her physical exam, were unremarkable. A trial of recombinant C1INH resolved an acute swell, so she was started on C1INH replacement, with significant reduction in her swell frequency. <h3>Discussion</h3> C1INH normal HAE continues to be difficult to diagnose with currently available assays. For patients with recurrent swells, not responding to mast cell stabilizers or antihistamines, a trial of recombinant C1INH or a bradykinin receptor antagonist, may aid in the diagnosis of C1INH Normal HAE.