Abstract
Background and study aims Endoscopic ultrasound (EUS) may be a useful modality for disease assessment and risk
stratification in ulcerative colitis. We assessed the reliability of a newly developed
EUS index of inflammation called the EUS-Ulcerative Colitis (EUS-UC) score.
Patients and methods The EUS-UC score components include total wall thickness, hyperemia, and depth of
inflammation (DOI). Three blinded expert endosonographers assessed EUS videos of 58
patients with UC in triplicate. Intra- and inter-rater reliability of the hyperemia
and DOI component scores were estimated using intra-class correlation coefficients
(ICCs). Total wall thickness reliability estimates could not be assessed in this study.
The ICCs were compared to the original indices from which they were derived.
Results For hyperemia, the inter-class ICC was “moderate” at 0.556 (95 % CI = 0.434–0.651)
and the intra class ICC was “almost perfect” at 0.884 (95 % CI = 0.835–0.920). The
newly defined hyperemia score performed better than the original index from which
is was derived. The DOI inter-class ICC was “fair” at 0.335 (95 % CI = 0.201–0.464),
and the intra-class ICC was “substantial” at 0.732 (95 % CI = 0.642–0.802). The DOI
reliability estimates were similar to the original index from which it was derived.
Conclusions The hyperemia component of the EUS-UC score performed significantly better than the
original index from which it was derived, but the reliability of the DOI component
was suboptimal. Intra-class correlation was excellent for both components. The EUS-UC
score is a promising instrument for assessment of UC and further validation is required.
