complementary procedure for surveillance colonoscopy in patients with the latter disease.
Recently, fluorescence endoscopy with 5-aminolaevulinic acid (5-ALA) sensitization has been shown to be a promising procedure for the detection of dysplasia in patients with UC. By this procedure, dysplastic lesions, which convert 5-ALA to protoporphyrin IX, can be observed as reddish areas under blue light. Messmann et al 6 reported that fluorescence endoscopy with various methods for sensitization had a sensitivity of 72.5% for the detection of dysplasia in patients with long-standing UC, in whom the prevalence of dysplasia was 40 (8.3%) of 481 biopsy samples. However, another group of investigators from Germany reported that they could identify 20 areas positive for 5-ALA fluorescence in 42 patients with inflammatory bowel diseases, all of which were negative for dysplasia. 7 In our case experience, we could show that AFI colonoscopy may be an alternative procedure to chromoscopy for the identification of possible dysplasia in UC. When our 2 cases were taken together, 6 of 11 lesions seen as dark magenta in color under AFI were dysplasia, whereas only 3 of 13 lesions depicted as green were dysplastic lesions, which were regarded as adenomas. However, it needs to be elucidated whether and to what specificity the procedure can differentiate neoplasia from inflammation in UC.