title: Correlation between endocytoscopy and conventional histopathology in microstructural features of ulcerative colitis.
abstract: BACKGROUND
  Routine diagnosis of the histopathological activity of ulcerative colitis (UC) requires multiple biopsy samples, and an endocytoscopy system (ECS) provides real-time ultra-magnifying microscopic imaging in vivo.
  
  
  METHODS
  We have established an ECS score (ECSS) to determine a histopathological activity index of UC. Fifty-five UC patients (mean age 40.7 years; 67% men) were enrolled. A super-magnifying ECS with magnification 450× was used, and sample biopsies were obtained. Matts' histopathological grade was determined, to evaluate disease severity, by two pathologists, with consensus. The ECSS of UC was independently determined by at least two investigators, with consensus. In total, 76 pairs of ECSS and Matts' histopathological grades were independently acquired. To validate the ECSS, inter-observer agreement between three endoscopists, with consensus, and another endoscopist, was calculated as the kappa value. We also evaluated the correlation between the ECSS and Matts' histopathological grade, and between the conventional Matts' endoscopic grade and Matts' histopathological grade.
  
  
  RESULTS
  The ECSS of UC intestinal mucosa, i.e., the sum of the indices for shape (0-3) and distance between crypts (0-2), and the visibility of superficial microvessels (0-1), showed a strong correlation with Matts' histopathological grades (ρ = 0.713, P < 0.001); as well, there was a strong correlation between the conventional Matts' endoscopic grade and Matts' histopathological grade (ρ = 0.694, P < 0.001). Furthermore, the ECSS showed high reproducibility (κ = 0.79, 95% confidence interval [CI] 0.71-0.87).
  
  
  CONCLUSIONS
  Our novel ECSS has good predictive value for the histopathological activity of UC.
authors.affiliation: Division of Gastroenterology and Hepatology, Department of Internal Medicine, Keio University School of Medicine, Tokyo 160-8582, Japan.
authors.forename: Rieko
authors.initials: R
authors.lastname: Bessho
authors.forename: Takanori
authors.initials: T
authors.lastname: Kanai
authors.forename: Naoki
authors.initials: N
authors.lastname: Hosoe
authors.forename: Taku
authors.initials: T
authors.lastname: Kobayashi
authors.forename: Tetsuro
authors.initials: T
authors.lastname: Takayama
authors.forename: Nagamu
authors.initials: N
authors.lastname: Inoue
authors.forename: Makio
authors.initials: M
authors.lastname: Mukai
authors.forename: Haruhiko
authors.initials: H
authors.lastname: Ogata
authors.forename: Toshifumi
authors.initials: T
authors.lastname: Hibi
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001706:Biopsy; D003093:Colitis, Ulcerative / Q000175:diagnosis* / Q000473:pathology; D016099:Endoscopy, Gastrointestinal / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008853:Microscopy / Q000379:methods*; D055806:Microvessels; D008875:Middle Aged; D015588:Observer Variation; D011237:Predictive Value of Tests; D011446:Prospective Studies; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D055815:Young Adult