Low frequency of colorectal dysplasia in patients with long-standing inflammatory bowel disease colitis: detection by fluorescence endoscopy.
OBJECTIVE
Patients with long-standing inflammatory bowel disease (IBD) have an increased risk of developing colonic dysplasias. Dysplastic changes in flat mucosa are likely to be missed by conventional colonoscopy. Endoscopic fluorescence imaging, using 5-aminolevulinic acid (5-ALA) as photosensitizer, has evolved as a new technique to differentiate between normal colonic mucosa and dysplasia. We combined this technique with random biopsies to prospectively evaluate the occurrence of dysplasias in patients with long-standing IBD.


METHODS
52 colonoscopies were performed in 42 consecutive patients (n = 28 with ulcerative colitis, n = 11 with Crohn's colitis, n = 3 with indeterminate colitis; mean age 43 years, range 21 - 78) with long-standing IBD colitis (median disease duration 14 years, range 3 - 40). All patients were in clinical remission. Patients were examined using both conventional white light and by fluorescence colonoscopy using oral 5-ALA. Four biopsies were taken every 10 cm from mucosa of normal appearance. In addition, macroscopically suspicious and fluorescence-positive areas were biopsied.


RESULTS
A total of 688 biopsies of red-fluorescent (n = 20) and nonfluorescent (n = 662) areas of mucosa were taken. Dysplasia was detected histopathologically in only two of the biopsies. These biopsies were taken from two polypoid lesions which were fluorescence-negative.


CONCLUSIONS
The rate of colonic dysplasia in patients with long-standing IBD colitis may be lower than previously reported.
Ochsenkühn
T
T
Department of Medicine II, Klinikum Grosshadern, University of Munich, Germany. thomas.ochsenkuehn@med.uni-muenchen.de
Tillack
C
C
Stepp
H
H
Diebold
J
J
Ott
S J
SJ
Baumgartner
R
R
Brand
S
S
Göke
B
B
Sackmann
M
M
D000284:Administration, Oral; D000328:Adult; D000368:Aged; D000622:Aminolevulinic Acid / Q000008:administration & dosage; D001706:Biopsy; D003092:Colitis / Q000473:pathology*; D003113:Colonoscopy / Q000379:methods*; D015179:Colorectal Neoplasms / Q000473:pathology*; D003937:Diagnosis, Differential; D005260:Female; D005453:Fluorescence; D006801:Humans; D008297:Male; D008875:Middle Aged; D017319:Photosensitizing Agents / Q000008:administration & dosage; D011230:Precancerous Conditions / Q000473:pathology*
D017319:Photosensitizing Agents; D000622:Aminolevulinic Acid