Rare manifestation of hypereosinophilic syndrome: Diffuse-type hair loss with massive perifollicular eosinophils.

A 46-year-old woman consulted our hospital with diffuse alopecia and blood eosinophilia. Histological examination of the scalp revealed dense eosinophilic infiltration around the hair follicles and in the surrounding subcutis. Oral corticosteroid was effective to reduce hair loss and blood eosinophilia, but these conditions immediately relapsed after ending treatment. In addition to alopecia, she had diarrhea and colitis showing histological findings of dense eosinophilic infiltrations in the submucosa. We diagnosed hypereosinophilic syndrome based on hypereosinophilia of blood and tissue with clinical symptoms of alopecia and diarrhea. We suppose diffuse alopecia showing massive eosinophilic infiltration around the hair follicle is a rare symptom of hypereosinophilic syndrome.