case_images: PMC8326450_01
case_images: Endoscopic and pathological findings in a patient with collagenous colitis in the active phase. (A) Colonoscopic examination revealed vascular networks without mucosal edema in the transverse colon. (B) Pathological examinations of the transverse colon biopsy samples revealed the presence of a subepithelial collagen band with a thickness >10mum (Masson's trichrome staining, bottom) and massive accumulation of immune cells in the lamina propria (hematoxylin and eosin, H&E staining, top). Scale bar, 100mum. Magnification x 400.
case_images: fmed-08-678268-g0001.jpg
case_images: PMC8326450_01_fmed-08-678268-g0001.jpg
case_images: F1
case_images: The colonoscopic examination revealed almost normal colonic mucosa from the ascending colon to the rectum (Figure 1A). Masson's trichrome staining (Figure 1B, bottom). Massive accumulation of immune cells in the lamina propria was observed (Figure 1B).
case_images: Endoscopic and pathological findings in a patient with collagenous colitis in the remission phase. (A) Colonoscopic examination revealed vascular networks without mucosal edema in the transverse colon. (B) Pathological examinations of the transverse colon biopsy samples revealed the absence of the subepithelial collagen band that was present during the active phase (Masson's trichrome staining, bottom), whereas the accumulation of immune cells in the lamina propria was still observed (hematoxylin and eosin, H&E staining, top). Scale bar, 100mum. Magnification x 400.
case_images: fmed-08-678268-g0002.jpg
case_images: PMC8326450_01_fmed-08-678268-g0002.jpg
case_images: F2
case_images: Follow-up total colonoscopy performed 5 months later revealed normal colonic mucosa from the rectum to the ascending colon (Figure 2A). By that time, the subepithelial collagen band almost disappeared, whereas immune cell infiltration into the colonic mucosa was still observed (Figure 2B).