Chapter 339: Diverticular Disease and Common Anorectal Disorders¶
Chapter 339 | Part 10: Disorders of the Gastrointestinal System
KEY CLINICAL POINTS¶
- Diverticulosis affects 50% of individuals >60 years, with 5% developing acute diverticulitis and 10–25% experiencing recurrent symptoms.
- Pseudodiverticula (most common in sigmoid colon) result from weak points in the colonic wall, with dysbiosis and low-grade inflammation contributing to pathogenesis.
- Hinchey staging classifies diverticulitis severity (Ia–IV), guiding surgical and medical management decisions.
- Fecal incontinence affects 15% of adults in the U.S., often linked to pelvic floor dysfunction, obstetric injury, or neurologic disorders.
- Hemorrhoids are classified by severity (I–IV) and managed with non-operative (rubber band ligation, sclerotherapy) or surgical techniques (hemorrhoidectomy, THD).
1. DEFINITION & OVERVIEW¶
Diverticular disease encompasses diverticulosis (presence of diverticula) and diverticulitis (inflammation/complication). Common anorectal disorders include rectal prolapse, fecal incontinence, and hemorrhoidal disease. Diverticulosis is more prevalent in developed countries due to Western diets, while rectal prolapse is six times more common in women.
Table 339-1: Presentation of Diverticular Disease¶
| Category | Symptoms | Complications |
|---|---|---|
| Uncomplicated Diverticular Disease (75%) | Abdominal pain, fever, leukocytosis, anorexia/obstipation | |
| Complicated Diverticular Disease (25%) | Abscess (16%), perforation (10%), stricture (5%), fistula (2%) |
Table 339-2: The Use of Fiber in the Management of Diverticular Disease (DD)¶
| Study | Intervention | Findings |
|---|---|---|
| Lancet, 1977 | Wheat/bran crisp bread | Significant reduction of symptoms score |
| BMJ, 1981 | Bran, ispaghula, placebo | No difference |
| J Gastroenterol, 1977 | Methylcellulose | Significant reduction in symptoms |
| Gastroenterology, 2012 | Fiber consumption | Fiber associated with great risk of DD |
| Study | Intervention | Findings |
|---|---|---|
| JAMA, 2008 | Nut, corn, popcorn consumption | Higher nut, corn, and popcorn had lower risk of recurrence |
1.1 Diverticulosis¶
Pseudodiverticula form at weak points in the colonic wall, most commonly in the sigmoid colon. Risk factors include NSAID use, smoking, sedentary lifestyle, and obesity. Fiber intake reduces risk, while high-fat diets increase it.
1.2 Rectal Prolapse¶
Full-thickness prolapse (procidentia) involves circumferential rectal wall protrusion through the anal canal. Mucosal prolapse is radial and associated with hemorrhoidal disease. Risk factors include pelvic floor weakness, childbirth, and aging.
1.3 Fecal Incontinence¶
Involuntary fecal passage or inability to control defecation. Common in older women and those with pelvic floor disorders. Neurogenic causes (e.g., stroke, MS) and structural defects (e.g., sphincter injury) contribute.
2. EPIDEMIOLOGY¶
Diverticulosis affects 50% of individuals >60 years, with 5% developing acute diverticulitis. Recurrent symptoms occur in 10–25%, and 10% progress to complications requiring surgery. Rectal prolapse is six times more common in women, peaking in women >60 years. Fecal incontinence prevalence is 15% in adults, rising with age and parity.
2.1 Diverticulosis¶
Incidence rises with age; 10–25% of patients with diverticular disease experience recurrent symptoms. Risk factors include NSAID use, smoking, obesity, and sedentary lifestyle.
2.2 Rectal Prolapse¶
Incidence peaks in women >60 years. 20% of children with rectal prolapse have cystic fibrosis. 30% of patients with internal rectal prolapse develop full-thickness prolapse.
3. ETIOLOGY & PATHOPHYSIOLOGY¶
Diverticula form at weak points in the colonic wall due to high intraluminal pressure and weak connective tissue. Dysbiosis and low-grade inflammation contribute to pathogenesis. Rectal prolapse results from pelvic floor weakness, while fecal incontinence stems from sphincter dysfunction or neurologic disorders.
3.1 Diverticulosis¶
Pseudodiverticula develop at points where vasa recta penetrate the muscularis propria, creating weak spots. Chronic inflammation and abnormal collagen cross-linking increase risk.
3.2 Rectal Prolapse¶
Full-thickness prolapse results from damage to pelvic floor nerves or repeated straining. Mucosal prolapse is radial and associated with hemorrhoidal disease.
3.3 Fecal Incontinence¶
Caused by sphincter dysfunction, neurogenic disorders (e.g., MS, stroke), or structural defects (e.g., obstetric injury). Pelvic floor weakness and rectocele contribute.
4. CLINICAL FEATURES¶
Diverticulitis presents with left lower quadrant pain, fever, and leukocytosis. Complications include abscesses, perforation, and fistulas. Fecal incontinence ranges from passive leakage to urge incontinence. Hemorrhoids present with bleeding, prolapse, or thrombosis.
4.1 Diverticulitis¶
Acute uncomplicated diverticulitis (75% of cases) presents with left lower quadrant pain, fever, and obstipation. Complicated cases (25%) may involve abscesses, perforation, or fistulas.
4.2 Fecal Incontinence¶
Symptoms include passive incontinence, urge incontinence, or fecal seepage. Associated with pelvic floor disorders, IBS, or neurologic conditions.
4.3 Hemorrhoids¶
Internal hemorrhoids (above dentate line) cause painless bleeding. External hemorrhoids (below dentate line) may thrombose, causing severe pain.
5. DIFFERENTIAL DIAGNOSIS¶
Diverticulitis must be differentiated from appendicitis, diverticulitis mimics, and other causes of abdominal pain. Fecal incontinence differentiates from IBS, IBD, or pelvic floor dysfunction. Hemorrhoids must be distinguished from anal fissures, tumors, or fistulas.
5.1 Diverticulitis¶
Differential diagnoses include appendicitis, diverticulitis mimics (e.g., colonic neoplasm), and other inflammatory bowel diseases.
5.2 Fecal Incontinence¶
Differentiate from IBS, IBD, neurogenic bladder, or pelvic organ prolapse.
5.3 Hemorrhoids¶
Distinguish from anal fissures, rectal tumors, or fistulas.
6. INVESTIGATIONS & DIAGNOSIS¶
CT scan is the gold standard for diagnosing diverticulitis. Anorectal manometry, pudendal nerve latency, and endoanal ultrasound evaluate fecal incontinence. MRI or cinedefecography assess rectal prolapse. Hemorrhoids are diagnosed via anoscopy.
Table 339-3: American Society of Anesthesiologists Physical Status Classification System¶
| Status | Description |
|---|---|
| P1 | Normal healthy patient |
| Status | Description |
|---|---|
| P2 | Mild systemic disease |
| P3 | Severe systemic disease |
| P4 | Severe systemic disease threatening life |
| P5 | Moribund patient |
| P6 | Brain-dead patient for donation |
6.1 Diverticulitis¶
Contrast-enhanced CT identifies sigmoid diverticula, thickened colonic wall, and pericolic fat inflammation. Hinchey staging guides management.
6.2 Fecal Incontinence¶
Digital rectal exam, anorectal physiology studies (manometry, PNTML), and MRI evaluate sphincter function.
6.3 Hemorrhoids¶
Anoscopy identifies internal/external hemorrhoids. MRI or cinedefecography assess prolapse.
7. MANAGEMENT & TREATMENT¶
Medical management includes fiber supplementation, antibiotics (for complicated diverticulitis), and biofeedback for fecal incontinence. Surgical options for diverticulitis include Hartmann’s procedure, laparoscopic resection, or percutaneous drainage. Hemorrhoids are managed with rubber band ligation, sclerotherapy, or hemorrhoidectomy.
Table 339-4: Outcome Following Surgical Therapy for Complicated Diverticular Disease Based on Modified Hinchey Staging¶
| Stage | Procedure | Anastomotic Leak Rate (%) | Overall Morbidity Rate (%) |
|---|---|---|---|
| Ia | Laparoscopic/open resection | 3 | 15 |
| Ib | Percutaneous drainage + resection | 3 | 15 |
| II | Percutaneous drainage + resection | 3 | 15 |
| III | Laparoscopic washout/draining | 3 | 30 |
| IV | Hartmann’s procedure | — | 50 |
Table 339-6: The Staging and Treatment of Hemorrhoids¶
| Stage | Description | Treatment |
|---|---|---|
| I | Enlargement with bleeding | Fiber, cortisone suppository, sclerotherapy |
| II | Protrusion with spontaneous reduction | Fiber, cortisone suppository, sclerotherapy |
| Stage | Description | Treatment |
|---|---|---|
| III | Protrusion requiring manual reduction | Fiber, cortisone suppository, rubber band ligation, operative resection |
| IV | Irreducible protrusion | Fiber, cortisone suppository, operative resection |
7.1 Diverticulitis¶
Uncomplicated cases: fiber, antibiotics (cephalosporin/metronidazole). Complicated cases: percutaneous drainage, laparoscopic resection, or Hartmann’s procedure.
7.2 Fecal Incontinence¶
Stool bulking agents, biofeedback, and sacral nerve stimulation. Severe cases may require sphincteroplasty or implantable devices.
7.3 Hemorrhoids¶
Non-operative: rubber band ligation, sclerotherapy. Surgical: Milligan-Morgan, PPH, or THD.
8. PROGNOSIS & COMPLICATIONS¶
Diverticulitis complications include perforation, peritonitis, and fistulas. Fecal incontinence may lead to depression and social withdrawal. Hemorrhoids may progress to thrombosis or anemia. Surgical risks include fecal incontinence, anal stenosis, and anastomotic leak.
8.1 Diverticulitis¶
Recurrence risk is 25% for diverticular bleeding. Complications include perforation, abscess, and fistula formation.
8.2 Fecal Incontinence¶
Long-term outcomes depend on sphincter repair success. Patients may experience depression and reduced quality of life.
8.3 Hemorrhoids¶
Complications include thrombosis, anemia, and progression to rectal prolapse.
9. SPECIAL CONSIDERATIONS¶
Pregnancy: Avoid NSAIDs and anticoagulants. Pediatrics: Cystic fibrosis screening in children with rectal prolapse. Elderly: Higher risk of perforation and anastomotic leak. Immunocompromised: Increased risk of diverticulitis complications.
9.1 Pregnancy¶
Avoid NSAIDs and anticoagulants. Monitor for perianal infections and hemorrhoids.
9.2 Pediatrics¶
20% of children with rectal prolapse have cystic fibrosis. Screen with sweat chloride test.
9.3 Elderly¶
Higher risk of perforation, anastomotic leak, and postoperative complications.
10. KEY POINTS & CLINICAL PEARLS¶
- Diverticulitis is managed with antibiotics (cephalosporin/metronidazole) and surgery for complications.
- Fiber supplementation reduces diverticulosis risk but may increase recurrence.
- Fecal incontinence requires anorectal physiology studies and sphincter repair.
- Hemorrhoids are staged I–IV; non-operative management is preferred for Grades I–II.
- Anorectal abscesses require drainage; fistulas are classified by sphincter involvement (intersphincteric, transsphincteric, etc.).