This 58 year old woman was referred for colonoscopy to evaluate a history of recent hematochezia and a significant family history of colon cancer. In the rectal vault, this ulceration was found just above the dentate line. The ulcer appears to be superficial with an irregular border and a fibrinous base. Prior to the procedure, she had related the history severe constipation and the periodic need for manual self-disimpaction. Biopsies taken from the periphery of the ulcer base revealed ulcerated rectal mucosa with a predominance of granulation tissue characterized by an admixture of small vessels, inflammatory cells, fibrin and edema. These findings are typical of a solitary rectal ulcer. Though poorly understood, the pathogenesis of this syndrome may involve several mechanisms. Pressure related ischemic injury from impacted stool as well as local trauma from repetitive self disimpaction could both be contributing factors. Defectograghy demonstrates a high proportion of patients with rectal prolapse and indeed the pathology of solitary rectal ulcer syndrome and rectal prolapse are very similar. Attempted therapies have included surgery, biofeedback, and a variety of medications.
Peter B. Kelsey, M.D., Harvard Medical School, Massachusetts General Hospital