LANGERHANS CELL HISTIOCYTOSIS OF THE STOMACH - A CAUSE OF GRANULOMATOUS GASTRITIS AND GASTRIC POLYPOSIS

Langerhans cell histiocytosis (LCH) of the alimentary tract is a rare condition, and LCH of the stomach especially so. We report a histologi cally and endoscopically unusual case of gastric LCH, the diagnosis of which was based on gastric mucosal biopsy specimens from an adolescen t with multiorgan LCH and striking gastric polyposis. Microscopically, the gastric mucosa was expanded by discrete granulomatous microaggreg ates of Langerhans cells, resulting in a close resemblance to other, m ore common nonnecrotizing granulomatous gastritides. The diagnosis of LCH was confirmed immunohistochemically and ultrastructurally. To our knowledge, this is the first report of gastric LCH with a granulomatou s histologic pattern, and the third to cause diffuse gastric polyposis . Langerhans cell histiocytosis should be included in the histologic d ifferential diagnosis of granulomatous gastritis, as well as in the en doscopic differential diagnosis of gastric polyposis.