Hereditary Angioedema Type III Estrogen-Sensitive: A Case Report and Literature Review

Hereditary angioedema (HAE) is a rare autosomal dominant disorder caused by excessive bradykinin production, leading to recurrent episodes of subcutaneous or submucosal edema. Type III HAE, primarily affecting women, is associated with hormonal factors such as estrogen, which exacerbate the frequency and severity of attacks. Unlike types I and II, this form lacks C1-inhibitor deficiency, making diagnosis challenging. We report the case of a 33-year-old pregnant woman (16 weeks of gestation) admitted with progressive upper lip edema. Her medical history revealed recurrent facial and neck edema triggered by oral estrogen-containing contraception, with no symptoms after its discontinuation. Genetic testing confirmed a heterozygous mutation in the F12 gene. The patient was treated with tranexamic acid, resulting in rapid symptom resolution. Type III HAE often requires targeted therapies such as icatibant or C1-inhibitor concentrates for acute attacks and tranexamic acid for prophylaxis, particularly in pregnancy. Patient education on self-administration of emergency treatments and family screening are essential to reduce morbidity. This case underscores the importance of recognizing estrogen-sensitive type III HAE, implementing tailored management strategies, and ensuring preventive measures to improve patient outcomes.