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Condition created 2026-08-19 · updated 2026-08-27
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Solitary Rectal Ulcer Syndrome (SRUS)

See Anorectal Physiology Testing and Rectal Prolapse (Procidentia) — SRUS overlaps mechanistically with internal rectal prolapse. Content below is from textbook reference chapters (Sabiston Ch52 - Pelvic Floor Disorders & Constipation and ASCRS Ch60 - Rectal Prolapse), not primary literature.

Overview

A rare, chronic benign disorder characterized by a combination of symptoms, clinical findings, and histologic abnormalities. Despite the name, 20% of patients have a single ulcer while 40% have multiple ulcers; the remainder have nonspecific lesions such as hyperemic mucosa or pseudopolyps.

Disorder of young adults (30–40 years), with a slight female predominance. Multifactorial cause, including internal rectal prolapse and abnormal/paradoxical contraction of the puborectalis muscle — both conditions cause trauma and compression of the anterior rectal wall on the upper anal canal during straining and defecation, with resulting mucosal ischemia and, in some cases, ulceration. Mechanistically, the leading edge of a prolapsing/intussuscepting rectum repeatedly traumatizes the mucosa as it invaginates downward, and the repeated trauma is speculated to cause the transient ischemia underlying ulceration.

Colitis cystica profunda (CCP) is a related disorder producing similar symptoms and a similar gross appearance to SRUS, thought to arise via the same mechanism: trauma from a cephalad-prolapsing segment of rectum can force mucosa beneath the surface, producing mucus-filled cysts. Biopsy distinguishes the two — see Diagnosis below.

Symptoms

Rectal bleeding, prolonged excessive straining, incomplete defecation/tenesmus, mucous discharge, perineal and abdominal pain, and constipation. Up to a quarter of patients are asymptomatic.

Diagnosis

Physical exam and anoscopy demonstrate an intrarectal prolapse and a 1–1.5 cm ulcer of the anterior rectal wall, 3–10 cm from the anal verge — sometimes difficult to differentiate from a rectal cancer on visual exam alone. On exam, thickened mucosa on the anterior rectal wall is typical, with frank ulcers seen in about 23% of cases and polyps/masses (rather than a discrete ulcer) in 74% — ulcers, when present, can be single or multiple, shallow, with hyperemic margins and a pale base. This uncommon condition's alarming appearance can be misdiagnosed as a polyp or even a cancer.

Histologic examination of biopsies shows characteristic findings that differentiate SRUS from cancer and other inflammatory lesions (IBD, ischemic colitis, infectious proctitis): fibromuscular obliteration of the lamina propria, hypertrophied muscularis mucosae with muscular fibers between the crypts, and glandular crypt abnormalities. Colitis cystica profunda (CCP) — the related disorder noted above — instead shows mucous cysts lined by columnar epithelium deep in the muscularis mucosa on biopsy; accurate pathologic evaluation is needed to distinguish the two. Endoanal ultrasonography typically shows a thickened internal anal sphincter in SRUS.

Workup for both SRUS and CCP includes a detailed history (straining, rectal bleeding, other anal symptoms) and endoscopy with biopsy. Defecography and anal manometry (see Anorectal Physiology Testing) are useful to guide treatment choice — specifically, to differentiate SRUS/CCP driven by pelvic floor weakness and internal prolapse from SRUS/CCP driven by straining and pelvic floor dyssynergia (see Constipation), since these two mechanisms lead to different treatment pathways (below).

Management

For patients with mild-to-moderate symptoms and no significant mucosal prolapse, medical treatment is usually effective: patient education and behavioral modification, high-fiber diet, stool softeners and bulking laxatives, avoidance of straining and/or anal digitation, minimizing time on the toilet, and use of sucralfate, corticosteroid, and/or mesalamine enemas. Argon plasma coagulation has also been described as a treatment modality, particularly useful to control bleeding. Pelvic floor physical therapy/bowel retraining is directed at normalizing the underlying defecatory disorder.

Whether surgery is appropriate depends on the underlying mechanism, refining the older "surgery is rarely indicated" framing:

  • SRUS/CCP secondary to pelvic floor weakness with internal prolapse or multicompartment pelvic organ prolapse can be offered surgical correction — a form of rectopexy (suture, mesh, or ventral), sometimes combined with urogynecology, per Rectal Prolapse Repair. A study found laparoscopic ventral rectopexy effective for SRUS specifically when associated with rectal prolapse.
  • SRUS/CCP secondary to straining and pelvic floor dyssynergia — surgical correction is not recommended; these patients benefit instead from pelvic floor physical therapy (see Constipation's dyssynergic-defecation treatment section).
  • For refractory, highly symptomatic patients where these approaches fail, local excision of the ulcer or a defunctioning stoma remain last-resort options.

Unfortunately, many patients with SRUS continue to have symptoms of anorectal dysfunction regardless of treatment.

Open items / gaps

  • ~~No primary trial data on medical therapy efficacy or surgical outcome comparisons.~~ Partially resolved by ASCRS Ch60 - Rectal Prolapse: the weakness-vs-straining treatment split is now sourced, and one named study supports ventral rectopexy for prolapse-associated SRUS — but no primary trial data exists yet for medical therapy (sucralfate/corticosteroid/mesalamine enemas, argon plasma coagulation) efficacy specifically.
  • The "many patients continue to have symptoms regardless of treatment" note is a notable but unquantified caveat — worth flagging to patients in counseling even without a specific number to cite.