title: Clear cell colitis: a form of microscopic colitis in children.
abstract: OBJECTIVE
  To describe a new clinical and pathological subtype of microscopic colitis in children.
  
  
  METHODS
  A selected group of children with abdominal pain, constipation and/or diarrhoea showing discrete or no macroscopic abnormalities on endoscopy was described.
  
  
  RESULTS
  Multiple biopsies of colon showed large mononuclear clear cells in lamina propria of mucous membrane provided that good quality histological sections were performed and observed under a higher magnification. Otherwise, they could be misinterpreted as artefacts. Their presence in routine histology might suggest a systemic storage disease (Whipple's disease), and neuronal intestine dysplasia. Using immunohistochemical staining and electron microscopy we confirmed their origin from CD68 positive mononuclear macrophages.
  
  
  CONCLUSIONS
  The presence of large clear cells is a constant microscopic feature. Failure of transient large bowel stationary macrophages plays a role in the pathogenesis of this benign microscopic clear cell colitis, sometimes coexisting with allergy.
authors.affiliation: Pediatric Division, City Hospital, 39-360 Nowa Deba, M. Curie Sklodowska 1, Poland.
authors.forename: Jan
authors.initials: J
authors.lastname: Józefczuk
authors.forename: Bogdan Marian
authors.initials: BM
authors.lastname: Wozniewicz
mesh_terms: D000293:Adolescent; D001706:Biopsy; D002648:Child; D002675:Child, Preschool; D003092:Colitis / Q000145:classification* / Q000473:pathology*; D003113:Colonoscopy; D005260:Female; D006801:Humans; D007223:Infant; D007413:Intestinal Mucosa / Q000473:pathology* / Q000648:ultrastructure; D008297:Male; D008854:Microscopy, Electron