He was initially suspected with hypereosinophilic syndromes or vasculitis such as eosinophilic granulomatosis with polyangiitis complicated by disseminated intravascular coagulation, and was treated with prednisone and thrombomodulin from hospital day 4 after bone marrow examination and the biopsies of the skin, stomach, and colon; however, these examinations excluded neoplastic hypereosinophilic syndromes and vasculitis. Here, THBD is linked to eosinophilic granulomatosis with polyangiitis.