title: Microscopic colitis with giant cells.
abstract: OBJECTIVE
  Collagenous colitis and lymphocytic colitis are the two types of microscopic colitis with specific morphological features. In this report we describe a new histopathological subtype of microscopic colitis.
  
  
  RESULTS
  Colonoscopy in four patients with chronic watery diarrhoea showed no macroscopic abnormalities. The random biopsies from the colon showed subepithelial multinucleated giant cells in combination with the features of collagenous colitis in three patients and lymphocytic colitis in one patient. These multinucleated giant cells were positive for CD68. The density of macrophages was highest in the most superficial part of the lamina propria. In one patient, a previous biopsy showed features consistent with collagenous colitis without multinucleated giant cells. Treatment with budesonide led to the disappearance of diarrhoea in all four patients.
  
  
  CONCLUSIONS
  The clinical and histopathological features of the four presented patients indicate that there exists a histopathological subtype of microscopic colitis characterized by the presence of subepithelial multinucleated giant cells, which probably arise from fusion of subepithelial macrophages. Analysis of more patients with this histopathological subtype of microscopic colitis is necessary to determine whether they also form a clinically distinct group.
authors.affiliation: Department of Pathology, Leuven University Hospitals, Leuven, Belgium. Louis.Libbrecht@uz.kuleuven.ac.be
authors.forename: L
authors.initials: L
authors.lastname: Libbrecht
authors.forename: R
authors.initials: R
authors.lastname: Croes
authors.forename: N
authors.initials: N
authors.lastname: Ectors
authors.forename: F
authors.initials: F
authors.lastname: Staels
authors.forename: K
authors.initials: K
authors.lastname: Geboes
mesh_terms: D000368:Aged; D015703:Antigens, CD / Q000032:analysis; D015214:Antigens, Differentiation, Myelomonocytic / Q000032:analysis; D003092:Colitis / Q000378:metabolism / Q000473:pathology*; D003094:Collagen / Q000378:metabolism; D005260:Female; D015726:Giant Cells / Q000737:chemistry / Q000473:pathology*; D006801:Humans; D007150:Immunohistochemistry; D008875:Middle Aged; D000097382:CD68 Molecule
chemical_list: D015703:Antigens, CD; D015214:Antigens, Differentiation, Myelomonocytic; D003094:Collagen; C067980:CD68 antigen, human; D000097382:CD68 Molecule