A Rare Case of Hereditary Angioedema in a 7-Year-Old Girl: Presentation, Diagnosis, and Bridging the Management Gap.

Abstract

Hereditary angioedema (HAE) is a rare, potentially life-threatening genetic disorder characterized by recurrent episodes of localized subcutaneous or submucosal swelling resulting from C1 esterase inhibitor deficiency or dysfunction. We report the case of a 7-year-old girl who presented with acute left-sided facial and upper lip edema that initially appeared as periorbital discoloration resembling ecchymosis following an upper respiratory tract infection. Her history included recurrent self-limited swelling episodes and an initially unrecognized family history of angioedema. Physical examination demonstrated nonpitting, nonpruritic facial edema without signs of airway compromise. Routine laboratory investigations were unremarkable. Complement testing subsequently confirmed HAE Type I, demonstrating markedly reduced C1 esterase inhibitor antigen and C4 levels with normal C1q concentrations. Because specific C1-INH replacement therapy was unavailable, the patient received fresh frozen plasma (approximately 15 mL/kg), resulting in complete clinical resolution within 3 days. This case highlights the diagnostic challenges of pediatric HAE, particularly when clinical manifestations mimic more common allergic, infectious, or traumatic conditions. It also illustrates the importance of early recognition, timely complement testing, and family screening for establishing the diagnosis. Furthermore, this report demonstrates that fresh frozen plasma may serve as an effective therapeutic alternative for acute attacks in resource-limited settings where targeted therapies are inaccessible. Early diagnosis, patient education, trigger avoidance, and appropriate long-term follow-up remain essential to reduce morbidity and prevent potentially life-threatening complications.