Mucosal atrophy in collagenous colitis: a case report.
BACKGROUND
Mucosal atrophy as a potential cause of impaired colonic compliance has not yet been described as a complication in Collagenous Colitis (CC).


METHODS
We present a 51-year-old female patient with a 20-year history of diarrhea and diagnosed with CC ten years prior to her presentation. We reviewed reports from three colonoscopies performed after the diagnosis. Overall 12 biopsies obtained in the last two colonoscopies were re-analyzed by two pathologists blinded to the aim of the study. Besides the typical histological findings of CC, the endoscopic appearance was normal, and no histological signs of atrophy were found during the first colonoscopy. Surprisingly, the second and third colonoscopy revealed a region of advanced segmental mucosal atrophy in the cecum with the mucosal height normalizing toward the transverse colon. This pattern of atrophy was inversely related to the pattern of sub-epithelial collagen deposition, which increased toward the rectum.


CONCLUSIONS
If no chance occurrence, our observation supports the idea that additional factors, probably luminal in nature, may be co-responsible for the mucosal atrophy in this case. Thus, mucosal atrophy in the proximal colon appears to be a new candidate among the growing list of rare complications associated with long standing CC.
Institute of Pathology, University of Bonn, Bonn, Germany.
Michael
M
Majores
Steffen
S
Wunsch
Bernd
B
Blume
Hans-Peter
HP
Fischer
Christoph
C
Reichel
D001284:Atrophy / Q000175:diagnosis; D001706:Biopsy; D046729:Colitis, Collagenous / Q000473:pathology*; D003113:Colonoscopy; D005260:Female; D006801:Humans; D007413:Intestinal Mucosa / Q000473:pathology*; D008875:Middle Aged