S8C20P7-2: The epidermis is thin and shows vacuolar changes at the dermal-epidermal interface; a basal unit is not represented. The papillary dermis is thin and hyalinized. Collagen bundles of the reticular dermis are reduced in diameter, and widely spaced in a mucinous matrix. There are mild perivascular infiltrates of lymphoid cells (Degos disease).

S8C20P7-5: This segment of bowel shows a surface layer of granulation tissue (green arrows); the mucosa is ulcerated. The muscularis propria is thin. The serosa is thickened (vertical dimensions are increased). Red arrows point to dilated, muscular vein with a mural thrombus. Blue arrows point to the neighboring muscular artery with fibrous obliteration of its lumen (Degos disease; same patient as seen in preceding images in this series of Pictorials). Conceptually, the changes in this area overlap with those of visceral Buerger’s disease; they are characterized by thrombotic occlusions that undergo organization.

S8C20P7-6: The vein (red arrows) and the occluded artery (green arrows) are shown at higher magnification. The mural thrombus is attached to the wall of the vein in the region of the yellow arrows.

S8C20P7-7: At a higher magnification, the media of the artery is best preserved just to the right of the center of the field. Red arrows point to a partially preserved, interrupted,  internal elastic lamina (Degos disease ).