Magnification endoscopy with optical chromendoscopy shows strong correlation with histologic inflammation in patients with inflammatory bowel disease

Background and aims: Apart from mucosal healing as an establishedtreatment goal in inflammatory bowel diseases (IBD), recent evidencesuggests that histologic healing may become another key prognosticparameter in IBD patients. We aimed to evaluate whether magnificationendoscopy with optical chromoendoscopy can accurately assesshistologic inflammation in IBD patients.Methods: In this prospective study, 82 IBD patients (30 UC, 52 CD) wereincluded. In all patients, magnification endoscopy in conjunction withoptical chromoendoscopy was performed and rated on a novelmagnification endoscopy score by three independent endoscopists.Targeted biopsies of the imaged areas were obtained and results werecompared against two histological scores in UC (Robarts HistopathologyIndex, RHI; Nancy Histology Index, NHI) and one score in CD (modifiedRiley index, mRI). Moreover, interobserver agreement was calculated.Results: Magnification endoscopy showed strong correlation withhistopathologic scoring in both UC (RHI: r=0.83, NHI: r=0.78, p<0.05)and CD (mRI: r=0.74, p<0.05) with high accuracy, sensitivity andspecificity. Further, 25% of patients with mucosal healing on standardendoscopy showed signs of microinflammation on magnificationendoscopy with optical chromoendoscopy, while none of the patientswith mucosal and vascular healing under magnification endoscopy withoptical chromoendoscopy exhibited microscopic inflammation.Interobserver agreement for grading intestinal inflammation bymagnification endoscopy with optical chromoendoscopy was substantial(κ>0.7).Conclusion: Magnification endoscopy in conjunction with opticalchromoendoscopy shows strong correlation with histologic inflammationin IBD patients. This approach holds the potential to reduce physicalbiopsies for monitoring of inflammatory activity in patients with IBDduring colonoscopy.