Two cases of angioedema without wheals induced by exercising or bathing

Dear Editor, Angioedema without wheals is caused by C1 inhibitor deficiency, drugs and various diseases but is rarely induced by a specific physical stimulus. Here, we report two cases of angioedema without wheals, clearly related to exogenous stimuli including bathing and exercising. Additionally, we examine fluctuations in plasma histamine levels and complement parameters before and after a challenge test. Case 1: An 18-year-old woman presented with a two-year history of recurrent episodes of eyelid swelling without wheals. The swelling occurred when bathing or exercising for approximately 30 min, persisting for two days before improving spontaneously. There were no subjective symptoms of hypohidrosis or other symptom-related factors such as drugs, foods, the timing of meals, season or her menstrual cycle but the high air temperature was a precipitating factor. She had atopic dermatitis (AD) as a child, but no history of urticaria or family history of angioedema.