Fig. 2

Clinical findings in KTS with anorectal and anorectosigmoid VM. VM develops with age, featuring as submucosal reticular phlebectasia in early stage (Panel A), and edematous, stiff and thickened gut by full thickness wall involvement in late stage (Panel B). Active bleeding sites usually can not be identified endoscopically. When sclerotherapy via imaging-guided direct puncture, we can see anorectal VM drains into internal iliac vein (IIV) (Panel C) (arrow), and/or into median sacral vein (Panel D) (arrow). Panel E shows trans-IIV (arrow) sclerotherapy for ablating rectal bleeding. Panel F: In a KTS patient with anorectosigmoid VM, trans-IIV phlebography demonstrated that part of VM drained into the superior rectal vein (arrow), which is indicative of portal vein system involvement. Panel G: Histopathologically, VM are dilated, thin-walled, sponge-like abnormal channels. Extensive venous thrombosis (asterisk) can be identified within the wall of affected colon