鼻前庭に生じた単発型若年性黄色肉芽腫の1例

Abstract

An 8-year-old girl complained of a nodule in her nasal vestibule. The nodule was a well-demarcated, dome-like, nodule, reddish-purple in color and elastic soft. The nodule was surgically excised for diagnostic and cosmetic reasons. Histological examination led to a diagnosis of juvenile xanthogranuloma. Juvenile xanthogranuloma is the most common type of non-Langerhans cell histiocytosis. It appears as benign, reddish-yellow, solitary or multiple nodules on the skin, commonly on the face, neck, scalp, or upper trunk. Xanthogranuloma occurs most frequently in infants and children, although adults may also be affected. It is not associated with metabolic abnormalities, hyperlipemia or diabetes but sometimes presents in association with neurofibromatosis and juvenile chronic myelogenous leukemia. No treatment is required because of its self-healing character, although isolated xanthogranulomas are often excised for diagnostic or cosmetic reasons. Xanthogranulomas that cause functional disorder may also be excised. Histologically, histiocytes densely infiltrate mainly the dermis. The cellular infiltrate includes giant cells, Touton cells, lymphocytes, eosinophils and neutrophils. The pathogenesis of xanthogranulomas is not clear, although it is generally considered a reactive granuloma caused by an unknown stimulus. Some reports have described isolated xanthogranulomas occurring at the site of an operation scar or insect bite, suggesting that an external stimulus may be involved in the pathogenesis of some xanthogranulomas. Xanthogranulomas in extracutaneous lesions and visceral involvement have also been reported, the most common extracutaneous site being the eye. Xanthogranulomas in the ear-nose-throat area are relatively rare. To our knowledge, the formation of a xanthogranuloma in the nose, especially in the nasal vestibule, is very rare. We report a rare case of isolated juvenile xanthogranuloma occurring in the nasal vestibule. We believe that an external stimulus may have been involved in the pathogenesis of xanthogranuloma in the present case, since children often touch their nasal vestibules with their fingers.