Digestive tract involvement in Langerhans cell histiocytosis. The French Langerhans Cell Histiocytosis Study Group.
BACKGROUND: Langerhans cell histiocytosis (LCH) is a rare disease with a wide clinical spectrum. Although little is known of gastrointestinal involvement in LCH, it may be a major clinical problem. We investigated clinical, pathologic, and immunohistochemical features of digestive tract LCH involvement in children. PATIENTS: Selection criteria consisted of the presence of LCH with digestive symptoms, and histologic confirmation of gastrointestinal involvement. Seven children (2%) met the criteria among 348 cases of LCH in a French national retrospective survey from 1983 to 1993. Two children whose LCH was diagnosed in 1994 were also selected. RESULTS: Nine children with LCH and digestive tract involvement were studied. Clinical features at presentation included skin (9/9) and mucosal (4/9) involvement, failure to thrive (5/9), diarrhea (7/9), bloody stools (4/7), vomiting (4/9), and hypoalbuminemia (8/9). Five of the nine children died; factors associated with a poor prognosis included young age, organ dysfunction (stage 4), and need for parenteral nutrition. Unlike control biopsy specimens, LCH cells of children with digestive tract involvement disclosed expression of the mucosal homing receptor integrin alpha 4 beta 7 on frozen skin and digestive tract biopsy specimens. CONCLUSION: Cutaneous, mucosal, and digestive tract involvement in LCH is a clinicopathologic entity. The prognosis and treatment of LCH depend on the extent of the disease; therefore the treatment of these disseminated forms should not be delayed. Thus children with cutaneous LCH and digestive symptoms should undergo digestive tract biopsies. Studies of homing receptors may contribute to our understanding of the mechanisms of dissemination in LCH.