Nonepisodic angioedema with eosinophilia after COVID-19 vaccination: a case successfully treated with reslizumab

BACKGROUND: Angioedema with eosinophilia (AE) is a rare allergic disease classified as episodic or nonepisodic. AE is characterized by angioedema, urticaria, fever, weight gain, and eosinophilia, but its etiology and pathogenesis have not yet been clarified. CASE PRESENTATIONS: We present a 70-year-old woman presented with generalized edema and urticaria after Moderna COVID-19 vaccination. Peripheral blood eosinophil count was marked elevated and echocardiography and Doppler ultrasonography of both the upper and lower extremities were unremarkable. Her symptoms and peripheral blood eosinophil count were improved after systemic steroid therapy, but she failed to respond to steroid tapering. Reslizumab (anti-interluekin-5) was administered intravenously, and she remained symptom free with a normal eosinophil count during 8 months of reslizumab treatment without steroids. CONCLUSIONS: We report a case of nonepisodic AE after COVID-19 vaccination that was successfully treated with reslizumab.