Angiolymphoid hyperplasia with eosinophilia presenting multinucleated cells in histology: an ultrastructural study

A case of angiolymphoid hyperplasia with eosinophilia arising on the face of a woman is reported. Histologically, the uniqueness of this case is the presence of multinucleated cells (MNCs), besides the conventional dermal changes. Electron microscopy showed that some of the apparent MNCs are clusters of endothelial cells forming immature vascular lumens with numerous microvilli, and the other MNCs displayed the recognized features of fibrohistiocytic or myofibroblastic cells. Immunohistochemically, some MNCs were positive for Ulex europaeus agglutinin and Factor VIII-related antigen. From these findings, some of the MNCs are histologically endothelial sprouts, and the others are fibrohistiocytic cells in the present case.