Vascular disease may lead to ischemic damage to the colon which hiterto has been thought to be confined to the proximal and descending colon and to spare the distal sigmoid and rectum. Studies here report a syndrome clinically, roentgenographically, and histologically recognizable as spontaneous ischemic disease of the rectum. In older persons, abdominal pain, alteration of bowel function, and rectal bleeding together with (1) the sigmoidoscopic appearance of bizarre nodular polypoid or ulcerative changes and (2) roentgenographic evidence of mucosal edema and ulceration with "thumb prints" characterize this syndrome and should raise the possibility of vascular injury to the lower bowel.
Kilpatrick ZM, Farman J, Yesner R, Spiro HM. Ischemic Proctitis. JAMA. 1968;205(2):74-80. doi:10.1001/jama.1968.03140280028008