Hypersegmentation of inflammatory cells in Langerhans cell granulomatosis

Langerhans cell granulomatosis (LCG) is characterized by a mixture of Lange rhans cells and eosinophils in varying proportions. The characteristic morp hology of Langerhans cells have already been described in many articles, bu r little attention has been paid to inflammatory cells. We examined sir cas es of Langerhans cell granulomatosis, which had originally been diagnosed a s eosinophilic granuloma. Inflammatory cells present in LCG showed hyperseg mentation. Twenty percent to 70% of eosinophils herd three or more segmente d nuclei, and 10-25% of neutrophils had five or more segmented nuclei. Such findings have never been described, and we believe hypersegmentation to be a feature of LCG. Furthermore, we emphasize that eosinophils in LCG mimic neutrophils in ethanol-fixed preparations, and thus may be a pitfall in mak ing a diagnosis in cytology and intraoperative consultation. (C) 2000 Wiley -Liss, Inc.