Classification of inflammation activity in ulcerative colitis by confocal laser endomicroscopy.
OBJECTIVE
The assessment of inflammation activity in ulcerative colitis (UC) includes endoscopy and histology. Confocal laser endomicroscopy (CLE) combines real-time endoscopy and histology. This study was aimed at evaluating the application of CLE in the assessment of inflammation activity in UC.


METHODS
In total, 73 consecutive patients with UC who visited Qilu Hospital for colonoscopy surveillance underwent CLE. Inflammation activity was first assessed by the colonoscopy Baron score, then by CLE with a 4-grade classification of crypt architecture, as well as by analysis of microvascular alterations and fluorescein leakage. Targeted biopsy samples were taken for histological analysis. Stored CLE images were subjected to post-CLE objective assessment.


RESULTS
Both assessment of crypt architecture and fluorescein leakage with CLE showed good correlations with histological results (Spearman's rho, both P<0.001). CLE seemed to be more accurate than conventional white-light endoscopy for evaluating macroscopical normal mucosa. More than half of the patients with normal mucosa seen on conventional white-light endoscopy showed acute inflammation on histology, whereas no patients with normal mucosa or with chronic inflammation seen on CLE showed acute inflammation on histology. Assessment of microvascular alterations by CLE showed good correlation with histological findings (P<0.001). On post-CLE objective assessment, subjective architectural classifications were supported by the number of crypts per image (P<0.001) but not fluorescein leakage results by gray scale (P=0.194).


CONCLUSIONS
CLE is reliable for real-time assessment of inflammation activity in UC. Crypt architecture, microvascular alterations, and fluorescein leakage are promising markers in CLE evaluation.
Li
Chang-Qing
CQ
Department of Gastroenterology, Qilu Hospital, Shandong University, Jinan, China.
Xie
Xiang-Jun
XJ
Yu
Tao
T
Gu
Xiao-Meng
XM
Zuo
Xiu-Li
XL
Zhou
Cheng-Jun
CJ
Huang
Wei-Qing
WQ
Chen
Hua
H
Li
Yan-Qing
YQ
D000328:Adult; D003093:Colitis, Ulcerative / Q000473:pathology*; D003113:Colonoscopy / Q000379:methods*; D005260:Female; D006801:Humans; D007249:Inflammation / Q000145:classification* / Q000473:pathology; D008297:Male; D018613:Microscopy, Confocal; D008875:Middle Aged