001390 - Acquired Angioedema due to C1-Inhibitor Deficiency – A Case Report

Acquired Angioedema due to C1-Inhibitor Deficiency – A Case Report

Background

Acquired angioedema due to C1-inhibitor deficiency (AAE-C1-INH) is a rare, potentially life-threatening condition characterized by recurrent subcutaneous and submucosal edema mediated by bradykinin. It typically presents in older patients and does not respond to conventional anti-allergic therapy, making early recognition and appropriate management essential.

Case Presentation

We report the case of an 81-year-old male patient with a history of arterial hypertension, diagnosed in 2023 with acquired angioedema due to C1-inhibitor esterase deficiency, based on low serum C4 levels and reduced C1-INH functional activity. The diagnosis was established in a specialized reference center in Târgu Mureș, Romania.

Symptoms had begun 3–4 years prior to diagnosis, with recurrent episodes of facial and tongue angioedema, unresponsive to corticosteroids, antihistamines, and adrenaline. The severity of airway involvement required emergency tracheostomy on two occasions. The patient experienced approximately two severe attacks per year, occasionally associated with abdominal pain.

He presented to the Emergency Department in Sibiu with marked edema of the left hemiface and tongue, accompanied by abdominal pain. On admission, the patient was in altered general condition, with significant facial and lingual edema, oxygen saturation of 97% on 3 L/min supplemental oxygen, blood pressure 130/97 mmHg, and heart rate 107 bpm. Laboratory findings showed mild hyperglycemia and a slight inflammatory response, with otherwise normal results.

Although treatment with C1-INH concentrate had previously been recommended, the patient had not obtained the medication. In the emergency setting, six units of fresh frozen plasma were administered without significant clinical improvement. Due to the high risk of glottic edema and potential need for orotracheal intubation or tracheostomy, the patient was admitted to the Intensive Care Unit. The clinical course was slowly favorable, with complete resolution of symptoms, and the patient was transferred to the internal medicine ward after 48 hours, asymptomatic.

This case highlights the diagnostic and therapeutic challenges of bradykinin-mediated acquired angioedema in elderly patients. Delayed diagnosis, lack of access to or non-adherence to specific therapy (C1-INH concentrate or icatibant), and reliance on ineffective conventional treatments significantly increase morbidity and the risk of life-threatening airway compromise.

Conclusion

Early recognition of acquired angioedema due to C1-inhibitor deficiency and timely initiation of targeted therapy are crucial to prevent severe complications and invasive airway procedures. Patient and caregiver education, along with close collaboration with specialized angioedema centers, is essential for optimal disease management.