DIGESTIVE-TRACT INVOLVEMENT IN LANGERHANS CELL HISTIOCYTOSIS

Background: Langerhans cell histiocytosis (LCH) is a rare disease with a wide clinical spectrum. Although little is known of gastrointestina l involvement in LCH, it may be a major clinical problem. We investiga ted clinical, pathologic, and immunohistochemical features of digestiv e tract LCH involvement in children. Patients: Selection criteria cons isted of the presence of LCH with digestive symptoms, and histologic c onfirmation of gastrointestinal involvement. Seven children (2%) met t he 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 ansi digestive tr act involvement were studied. Clinical features at presentation includ ed skin (9/9) and mucosal (4/9) involvement, failure to thrive (5/9), diarrhea (7/9), bloody stools (4/7), vomiting (4/9), and hypoalbuminem ia (8/9). Five of the nine children died; factors associated with a po or 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 t he 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; th erefore the treatment of these disseminated forms should not be delaye d. Thus children with cutaneous LCH and digestive symptoms should unde rgo digestive tract biopsies. Studies of homing receptors may contribu te to our understanding of the mechanisms of dissemination in LCH.