case_images: PMC10838215_01
case_images: Contrast-enhanced computed tomography revealed a short segment dilatation of the jejunal loop with loss of valvulae conniventes (red arrow). No mesenteric vessel thrombus was noted.
case_images: cureus-0016-00000051676-i01.jpg
case_images: PMC10838215_01_cureus-0016-00000051676-i01.jpg
case_images: FIG1
case_images: Importantly, mesenteric vessel thrombosis was absent in the contrast imaging (Figure 1).
case_images: A. Gross photography displayed dilatation of the proximal jejunal segment without serosal exudates, perforation, or fat creeping. B. The mucosa exhibited loss of valvulae conniventes with a serosal adhesion between the proximal dilated segment and the distal unremarkable bowel loop.
case_images: cureus-0016-00000051676-i02.jpg
case_images: PMC10838215_01_cureus-0016-00000051676-i02.jpg
case_images: FIG2
case_images: The mucosa of the proximal dilated segment appeared flattened without signs of perforation, hemorrhagic necrosis, creeping fat, or gangrene (Figure 2). 
case_images: A. Low-power magnification showing a thickened wall of small-calibre subserosal arteries and veins (H&E,40x) B. High-power magnification exhibiting smooth muscle collarette around the tunica media of a subserosal artery (H&E, 200x) C. Smooth muscle collarette around the tunica media of a subserosal vein (H&E, 200x) D. Smooth muscle actin immunohistochemistry highlighting the smooth muscles around the tunica media of subserosal arteries and veins (SMA IHC 40x) E. Smooth muscle actin immunohistochemistry highlighting the smooth muscles around the tunica media of a subserosal artery (SMA IHC 200x) F. Verhoeff-van Gieson stain demonstrating disruption of the internal elastic lamina (black arrow) and intimal hyperplasia (VVG stain, 400x) G. Uninvolved medium-sized mesenteric artery and vein away from the bowel wall (H&E, 40x) H. Representative sections from the flattened mucosa show pyloric gland metaplasia with a thick muscularis mucosa. No significant inflammation, cryptitis, crypt distortion, or basal plasmacytosis was noted (H&E, 40x)
case_images: cureus-0016-00000051676-i03.jpg
case_images: PMC10838215_01_cureus-0016-00000051676-i03.jpg
case_images: FIG3
case_images: Microscopic examination demonstrated smooth muscle collarettes arranged radially around the tunica media of small-calibre arteries and veins in the subserosa (Figure 3A, 3B, 3C), as highlighted by smooth muscle actin (SMA) immunohistochemistry (Figure 3D, 3E). Van Gieson staining underscored the disruption of the internal elastic lamina of a small-calibre subserosal artery with intimal hyperplasia (Figure 3F). Medium-sized mesenteric arteries and veins located away from the bowel wall appeared unaffected (Figure 3G). The mucosa exhibited prominent pyloric gland metaplasia with thickened muscularis mucosae, while no significant inflammation, cryptitis, crypt abscess, crypt distortion, crypt loss, granuloma, or basal plasmacytosis were noted (Figure 3H).