Can a Patient with a Colostomy Still Defecate from the Rectum?
Whether a patient with a colostomy can still defecate from the rectum depends entirely on the type of colostomy and whether the distal bowel (rectum and anus) remains in continuity with the fecal stream.
Understanding Colostomy Types and Rectal Function
End Colostomy (Complete Diversion)
- An end colostomy completely diverts the fecal stream, meaning NO stool will pass through the rectum 1
- The distal colon and rectum are either removed or completely bypassed, eliminating any possibility of rectal defecation 1
- This is the most common permanent colostomy configuration and is specifically designed to prevent fecal passage through the anus 1
Loop Colostomy (Temporary/Partial Diversion)
- A loop colostomy may allow some stool or mucus to pass through the rectum, though this is typically minimal 2
- The distal bowel remains in continuity but receives little to no fecal content 2
- Patients may experience passage of mucus, blood, or occasionally small amounts of stool from the rectum even with a functioning loop colostomy 2
Clinical Scenarios Where Rectal Passage Occurs
Pre-Treatment Colostomies
- Approximately 10%-20% of anal cancer patients require a pre-treatment colostomy for symptom management 1
- These colostomies are typically permanent because the high radiation dose to anal sphincters causes persistent fecal incontinence or anal stenosis 1
- Closure or reversal should be considered the exception and only if the anorectum is functionally intact 1
Distal Stump Complications
- Patients with end colostomies and retained rectal stumps may experience discharge of mucus from the rectum, which is normal 2
- This is NOT fecal defecation but rather mucus production from the remaining rectal mucosa 2
- Distal fecal impaction can occur if the stomas are mislocated or if a loop configuration allows some fecal passage 2
Key Clinical Pitfalls
Common misconception: Patients and providers sometimes confuse mucus discharge with actual bowel movements 2
Critical distinction:
- Normal colostomy output is formed stool occurring once daily through the stoma 3
- Any rectal discharge in a patient with an end colostomy represents mucus, not stool 2
- If actual formed stool passes rectally with a colostomy in place, this indicates either a loop configuration or colostomy malfunction 4, 2
Functional Outcomes After Colostomy Closure
- When colostomies ARE reversed (in appropriate cases), 92% of patients can achieve successful defecation per rectum without fecal incontinence 5
- However, colostomy closure is only feasible when the distal rectum and anal sphincters remain functionally intact 1, 5
- After radiation therapy or sphincter damage, the likelihood of successful closure drops dramatically 1