CT of Kimura disease.

Kimura is credited with first describing a condition-eosinophilic granuloma of the soft tissue-that subsequently has been given his name. Since then, more than 500 cases have been reported in review series, mainly in the Chinese and Japanese literature [1]. The disease occurs only in Orientals, and more than 80% of these patients are male. Presentation may occur over a wide age range, but it is most common in the second and third decades. Symptoms may fluctuate during periods of many years. The presenting feature is usually swelling in the region of the salivary glands and local lymphadenopathy. Locally, erythema and induration of the overlying skin may be present, along with a papular or follicular rash . Less common sites include all extracranial softtissue areas of the head and neck, with rare involvement of the axilla, groin, popliteal region, forearm , hand, and spermatic cord [2 , 3]. The lesion is usually solitary, but multiple and disseminated lesions have been reported . Characteristically the peripheral blood eosinophilia reaches 30%-40%. Increased serum lgE has also been observed. These findings suggest an allergic or parasitic cause, but searches for Ankylostoma, Ascaris, and many other organisms have been unsuccessful [1 ); so, the etiology remains unknown. Histologic examination shows heavy lymphocytic and eosinophilic infiltration with vascular proliferation and fibrosis. Lymphoid tissue is hyperplastic. Other lesions similar to Kimura disease have been described. Of these, angiolymphoid hyperplasia with eosinophilia (ALHE) is the most common. This condition differs in that (1) it affects non-Orientals , frequently women in an older age group; (2) there is involvement of more superficial subcutaneous tissues; (3) generally no lymphadenopathy is present; (4) peripheral eosinophilia is less marked; (5) vascular proliferation is more prominent; and (6) fibrosis is not a feature. Less common lesions with similar histologic features form a spectrum of disorders, and there is continuing debate in the literature as to whether these should all be classified as ALHE or whether they are distinct entities. For the present, Kimura disease has been placed under this general heading [4-6). Kimura disease must not be confused with eosinophilic granuloma, which is never associated with peripheral eosinophilia. Previous radiologic investigations of Kimura disease were confined to radiographs and were essentially unhelpful.