Clinical Science Histomorphological Assessment of Phlebitis in Renal Allografts

Results Small interlobular veins were composed of endothelium and basement membrane, similar to capillaries, while the walls of large interlobular and arcuate veins had smooth muscle cell bundles forming the medial layer, similar to large extrarenal veins. In the control group, only focal mononuclear infiltration around small interlobular veins was found (8/31). In rejected kidney allografts, the veins were frequently infiltrated with inflammatory cells, predominantly T lymphocytes and macrophages (29/29). Other changes included thrombosis (16/29), fibrinoid necrosis (7/29), and sclerosis (9/29), and in one case an intimal lipid deposition.