Fig. 1

Representative endoscopic and histologic findings before and after vedolizumab therapy in patients who had good response. (a, b) Endoscopic presentations before vedolizumab therapy showing diffuse erythema and focal punctate mucosal ulcerations. (c, d) Endoscopic presentations from the same patients after vedolizumab therapy showing normal mucosa. (e) Before vedolizumab therapy, chronic active colitis with cryptitis and crypt abscesses in the background of lamina propria expansion by lymphoplasmacytic infiltration, basal lymphoplasmacytosis, and architecture distortion. (f) After vedolizumab therapy, chronic colitis with architecture distortion and glandular dropout without active colitis. Chronic infiltrates in the lamina propria were markedly reduced to almost normal