Colon involvement in Langerhans' cell histiocytosis

Background: Langerhans' cell histiocytosis (LCH), a granulomatous disorder of unknown cause, most often affects the bony skeleton and skin. Obvious gu t involvement is uncommon, and colon involvement has been cited in only a s mall number of case reports, probably because most patients who have LCH wi th diarrhoea and/or failure to thrive are not investigated by colonoscopy a nd biopsy. The current study was conducted to determine the incidence of sy mptomatic colon involvement among patients with multisystem LCH treated at a single institution. Method: A retrospective review of cases in hospital records and the literat ure. Results: Of the 275 children with LCH in the database, 5 were identified as having biopsy-confirmed colonic involvement. Another 14 cases were identif ied by a literature review. Conclusion: Colonic involvement in patients with multisystem LCH is probabl y more common than currently recognised. In addition to the other investiga tions recommended by the Writing Group of the Histiocyte Society, it is rec ommended that patients with any symptoms suggestive of gut involvement unde rgo colonoscopy and biopsy of the colonic mucosa.