Clinical relevance of endoscopic assessment of inflammation in ulcerative colitis: Can endoscopic evaluation predict outcomes?

Table 1 Disease activity indices with endoscopic component alone

Disease activity index	Endoscopic variables
Baron score[14]	Bleeding and MVP
1964
Rachmilewitz endoscopic index[18]	Granulation, MVP, Mucosal vulnerability, Mucosal damage
1989
UC colonoscopic index of severity (UCCIS)[19]	MVP, Granularity, Ulceration, Bleeding, Segmental assessment of endoscopic severity, Global assessment of endoscopic severity
2013
UC endoscopic index of severity (UCEIS)[13]	MVP, Bleeding, Erosions and Ulcers
2013

MVP: Mucosal vascular pattern; UC: Ulcerative colitis.

Table 2 Disease activity indices with endoscopic and non-endoscopic components

Disease activity index	Endoscopic variables	Non-endoscopic variable
Powell-Tuck score[20]	Bleeding	Wellbeing, Abdominal pain, stool frequency and consistency, Bleeding, Anorexia, nausea and vomiting, EIM, Temperature
1982
Sutherland index[21]	Friability, Bleeding	Stool frequency, Bleeding, Physician’s rating of disease activity
1987
Mayo score[16]	Erythema, MVP, Friability, erosions, ulcers, spontaneous bleeding	Stool frequency, Bleeding, Physician’s global assessment
1987
Improvement based on individual symptom scores[22]	Mucosal oedema, MVP, Granularity, Friability, Petechiae, Ulceration, Spontaneous bleeding	Rectal bleeding, Stool frequency, Abdominal pain, PFA, PGA
2002

EIM: Extra-Intestinal Manifestations; MVP: Mucosal vascular pattern; PGA: Physician global assessment; PFA: Patient functional assessment.

Table 3 Correlation of endoscopic activity with clinical symptoms

Ref.	Study characteristics	Results
Karoui et al[35]	Prospective observational study.	CRP correlated well with DAI and Rachmilewitz score
2011	101 patients with UC in remission.	Correlation between DAI and Rachmilewitz was not statistically significant
Tunisia	CRP, Disease activity index and Rachmilewitz scores used
Osada et al[36]	Prospective observational study.	Clinical symptoms correlated with left sided disease activity.
2008	54 patients with UC.	CRP and ESR correlated well with right sided inflammation.
Japan	CRP, ESR, Mayo endoscopic subscore, Lichtiger’s clinical activity scores used.
Turner et al[37]	Prospective observational study.	Disease activity was best assessed by Walmsley and PUCAI followed by Partial Mayo score and Rachmilewitz
2009	86 patients with UC. Disease activity was measured using 9 different activity indices
Canada

CRP: C-reactive protein; DAI: Disease activity index; ESR: Erythrocyte sedimentation rate; PUCAI: Paediatric ulcerative colitis activity index; UC: Ulcerative colitis.

Table 4 Correlation between white light endoscopy and histology in ulcerative colitis

Ref.	Study characteristics and aims	Results
Bitton et al[8]	Prospective observational study	36.4% patients relapsed
2001	74 patients in clinical and endoscopic remission were included	Younger age, multiple previous relapses (women), and basal plasmacytosis on histology predicted relapse.
United States	Followed up for a year or until the patients relapsed.	CRP, ESR, IL-1b, -6, 15, ANCA was non-predictive of relapse.
Azad et al[41]	Prospective observational study	57.7% patients relapsed
2011	26 patients with clinical and endoscopic remission were included	Increased Eosinophils and Neutrophils were predictors of relapse.
India	Monthly follow up for a year or until the patients relapsed.	Hb, CRP, ESR, IL-6 were not predictive of relapse.
Bessissow et al[7]	Retrospective study	Microscopic inflammation was found in 40% of patients.
2012	75 patients with endoscopically inactive disease (Mayo score 0)	Basal plasmacytosis and histological activity (Geboes score ≥ 3.1) predicted relapse.
Belgium	Time to relapse was noted
Lemmens et al[40]	Retrospective study	Significant correlation with Mayo endoscopic subscore and histology noted in extremes of disease (inactive and acute severe disease)
2013	131 patients with known UC
Belgium	Correlation of endoscopy and histology
Rosenberg et al[5]	Prospective observational study	54% of patients with quiescent disease had signs of histological inflammation.
2013	103 UC patients in clinical remission
United States	Correlation of endoscopy and histology
Feagins et al[6]	Retrospective study of 51 patients.	20% of patients had flare up within 12 mo.
2013	colonoscopy for surveillance	Basal lymphocytosis, disruption of crypt architecture, erosions and ulcers predicted relapse.
United States	Correlation of endoscopic and histological activity
Zenlea et al[42]	Prospective study	23% of patients relapsed
2016	179 patients included	Histological activity with Geboes score ≥ 3.1 was strongest predictor of relapse.
United States	Baseline Mayo endoscopic score and Geboes score for histology noted
	Follow up period was 12 mo

UC: Ulcerative colitis; Hb: Haemoglobin; CRP: C-reactive protein; ESR: Erythrocyte sedimentation rate; IL-6: Interleukin-6; ANCA: Anti-nutrophil cytoplasmic antibody.

Table 5 Relapse prediction using advanced imaging techniques

Ref.	Imaging modality	Study characteristics	Results
Watanabe et al[9]	Magnification colonoscopy with chromoendoscopy	Prospective study	70% of patients with mucosal defects identified by MC had a flare up within 12 mo
2009		57 patients with clinical and endoscopic remission were enrolled for MC examination and followed up for 12 mo
Japan
Nishio et al[10]	Magnification colonoscopy with chromoendoscopy	Prospective study	29% of patients relapsed. Significant correlation seen between pit pattern abnormalities and relapse rate.
2006		113 patients with UC in remission were enrolled. Pit pattern in rectal mucosa assessed using MC. Followed up for 12 mo
Japan
Fujiya et al[11]	Magnification colonoscopy	18 patients with UC in remission underwent MC and follow up	7 out of 9 (77.7%) with minute epithelial defect had a flare.
2002
Japan
Kudo et al[46]	NBI	Prospective study	Obscured MVP had good correlation with the histological activity.
2009		157 colonic segments among 30 patients were examined under WLE and NBI
Japan
Jauregui-Amezaga et al[49]	Chromoendoscopy and NBI	Prospective study	27% relapsed during follow up
2014		64 patients with clinical and endoscopic remission for at least 3 mo were included. 1 year follow up.	Neither NBI nor chromoendoscopy predicted relapse
Spain
Osada et al[55]	AFI	Retrospective study	The green component of AFI correlated closely with the inflammatory activity
2011		572 images from 42 patients were correlated with histological activity
Japan

MC: Magnification colonoscopy; MVP: Mucosal vascular pattern; AFI: Autofluorescence imaging; NBI: Narrow band imaging.