Angiolymphoid hyperplasia with eosinophilia simulating lymphadenopathy.

A case of angiolymphoid hyperplasia (AHE) with eosinophilia presenting with recurrent inguinal swellings simulating lymphadenopathy is described. Tissue was examined by light microscopic techniques, electron microscopy and immunohistochemistry. Electron microscopy showed large numbers of cytoplasmic filaments and bizarre Weibel-Palade bodies in the atypical endothelial cells that characterize AHE. Factor VIII related antigen was demonstrated in a small proportion of these cells by immunoperoxidase staining. The absence of staining for lysozyme and alpha 1 antitrypsin does not support the concept that these cells are histiocytic in nature. The prominent lymphoid and plasma cell proliferative elements in this case showed a polytypic staining pattern for immunoglobulin. An unusual reticular staining pattern for IgE was observed in the lymphoid follicles. The nature and pathogenesis of AHE is discussed in the light of previous publications and the findings in this case.