Abstract

Infantile form of histiocytosis X is commonly presented as multiorgan desseminated form such as Letterer-Siwe disease. Lymph node involvement of histiocytosis X is usually accompanied by adjacent bone or skin lesion. Solitary nodal eosinophilic granuloma without evidence of other organ involvement is very rare. A case herein report is a 11 month-old female infant presented with fever and palpable both inguinal lymph nodes. There was neither skin lesion nor hepatosplenomegaly. Laboratory evaluation was within normal range except increased alkaline phosphatase and many neutrophils in urine. Radiologic examination revealed no remarkable bone lesions. And she showed good clinical outcome without evidence of other organ involvements. On microscopic examination of inguinal lymph node it was replaced by infiltration of histiocytes mainly along the sinusoid. Some of histiocytes showed morphologic features of "histiocytosis X cell" having nuclear grooves or multilobulation. Multinulceated giant cells were frequently see. Numerous eosinphils were also infiltrated and showed multifocal microabscess formation. Immunohistochemical staining revealed that majority of histiocytes were postitive for S-100 protein but multinucleated histriocytes, phagocytic histiocytes and those around the abscess were positive for macrophage marker, suck as CD68 and alpha-1-antichymotrypsin. Interestingly some histiocytes showed positivity for both S-100 protein and macrophage marker. These results suggest that histiocytosis X is proliferative disorder of phenotypically heterogenous population of histiocytes in contrast to the theory that it is a proliferative disorder of Langerhans cells.

• Keywords: Histiocytosis X;Eosinophilic granuloma;Lymph node;