Basics
Description
- Micro- or macroscopic perforation of diverticulum
- Uncomplicated (75%) vs. complicated
- Incidence increasing
Etiology
- Fecal material in diverticulum hardens, forming fecalith, increasing intraluminal pressure
- Erosion of diverticular wall leads to inflammation
- Focal necrosis leads to perforation
- Microperforation: Uncomplicated diverticulitis:
- Colonic wall thickening
- Inflammatory changes (fat stranding on CT)
- Macroperforation: Complicated diverticulitis:
- Abscess
- Bowel obstruction
- Fistulas after recurrent attacks
- Colovesical fistula (most common) presents with dysuria, frequency, urgency, pneumaturia, and fecaluria.
- Peritonitis
Diagnosis
Signs and Symptoms
History
- Symptoms typically develop over days
- Almost 50% have had prior episodes of pain
- Left lower quadrant pain in 70% of cases in Western countries
- Initially vague, then localizes
- RLQ in 75% of Asian patients
- Nausea/vomiting, constipation, diarrhea, urinary symptoms (in decreasing order)
Physical Exam
- +/- low-grade fever
- Tenderness at left lower quadrant with occasional (20%) mass palpated (phlegmon):
- Phlegmon-inflamed bowel loops or abscess
- Abdominal distension
- Bowel sounds variable
- Rectal tenderness with heme-positive stool:
- Massive gross rectal bleeding (rare)
- Peritoneal signs if:
- Unremarkable exam if:
- Elderly
- Immunocompromised
- Taking corticosteroids
Essential Workup
- CBC
- UA
- Blood cultures and lactate
- If showing signs of sepsis
- CT of abdomen/pelvis
- Preferred diagnostic modality
- Ability to diagnose nondiverticular causes of abdominal pain
- Accuracy enhanced with use of IV and PO/PR contrast
- Gastrografin PO/PR (per rectum) contrast may be used; avoid barium, especially when perforation is suspected
- Plain radiographs: Chest/abdomen
Diagnosis Tests & Interpretation
Lab
- CBC
- Leukocytosis common, but absence does not exclude diagnosis
- UA
- Sterile pyuria is possible
- Colonic flora (bacteria) suggests colovesical fistula
Imaging
- Abdominal (supine and upright) and chest radiographs
- Perforation indicated by free air
- Obstruction indicated by air-fluid levels
- CT
- Diagnostic criteria include:
- Wall thickening >5 mm
- Inflammation of pericolic fat
- Pericolic abscess
- Nondiagnostic criteria include:
- Stricture
- Diverticula
- Fistula
- CT-guided percutaneous needle aspiration of localized abscesses avoids further surgery.
- Endoscopy
- Not necessary to diagnose acute illness
- Rigid sigmoidoscopy aids in diagnosing nondiverticular causes of abdominal pain (spasm, stricture, edema, pus, or peridiverticular erythema).
- US
- For diagnosing colonic wall thickening, inflammation, mass, abscess, or fistula
- Greatly operator dependent
- Not reliable in presence of intestinal gas
- Barium enema
- Indicated after resolution of acute illness to rule out fistula or other colonic pathology (e.g., carcinoma)
Differential Diagnosis
- Colon carcinoma with perforation
- Ischemic colitis
- Bacterial colitis
- Appendicitis
- Left-sided pain if peritonitis from ruptured appendix
- Right-sided diverticular pain with cecal diverticulum (rare) or redundant sigmoid colon
- Inflammatory bowel disease
- Irritable bowel syndrome
- Ruptured or torsed ovarian cyst
- Pancreatic disease
- Pelvic inflammatory disease
- Peptic ulcer disease
- Renal colic
Treatment
Pre-Hospital
IV fluids
Initial Stabilization/Therapy
- Fluid resuscitation with 0.9% normal saline
- Bowel rest
- NPO or clear liquid diet
- Nasogastric tube (NG) tube if persistent vomiting or bowel obstruction suspected
Ed Treatment/Procedures
- Uncomplicated diverticulitis
- Most respond to medical therapy, but 30% may require surgery
- Complicated diverticulitis
- Most require percutaneous drainage or surgery
- Analgesia
- Anticholinergics (dicyclomine):
- Reduces colonic spasm
- Does not mask underlying pathology
- Opiates for more aggressive pain management (theoretically increase intraluminal pressure, leading to perforation)
- Do not use if hemodynamically unstable
- Antibiotics to cover gram-negative aerobic and anaerobic bacteria:
- Mild, uncomplicated cases (peridiverticulitis) for outpatient management:
- Ciprofloxacin or levaquin + metronidazole or clindamycin
- Trimethoprim/sulfamethoxazole (TMP/SMX) DS + metronidazole
- Amoxicillin/clavulanate
- Duration of therapy is 10-14 days
- Moderate uncomplicated and mild complicated cases for inpatient management:
- Ceftriaxone or other 3rd-generation cephalosporin + metronidazole or clindamycin
- Ampicillin/sulbactam
- Piperacillin/tazobactam
- Ticarcillin/clavulanate
- Ciprofloxacin or levaquin + metronidazole or clindamycin
- Aztreonam
- Complicated cases (with peritonitis from perforation), consider:
- Imipenem/cilastatin
- Meropenem
- Aztreonam + metronidazole or clindamycin
- Gentamicin + metronidazole or clindamycin ± ampicillin
- Trovafloxacin (alternative)
- Surgery:
- Emergent surgery:
- Indicated for generalized peritonitis from perforation
- 2-stage procedure with resection of diseased segment of colon and proximal colostomy followed later with reanastomosis
- Elective surgery:
- Indicated for multiple recurrent attacks (>2) without generalized peritonitis (controversial); fistula formation; intractable pain; unresolved obstruction; failure of medical therapy; single serious attack in patient <50 yr of age (controversial)
- 1-stage procedure following resolution of inflammation from medical therapy
- Nonoperative management may be considered for complicated diverticulitis.
- Peridiverticular abscess drainage:
- Indicated if well circumscribed and easily accessible
- Accomplished by CT- or ultrasound-guided percutaneous needle aspiration
- Outpatient therapy:
- Clear liquids with follow-up in 2-3 days
- When acute condition has resolved:
- High-fiber, low-fat diet to decrease recurrence of attacks
Medication
- Amoxicillin/clavulanate: 500/125 mg PO TID or 875/125 mg PO BID
- Ampicillin: 2 g IV q6h
- Ampicillin/sulbactam: 3 g IV q6h
- Cefotetan: 2 g IV q12h
- Cefoxitin: 2 g IV q8h
- Ciprofloxacin: 400 mg IV q12h or 500 mg PO BID
- Dicyclomine: 20 mg PO QID (up to 40 mg PO QID) or 20 mg IM q6h (not for IV use)
- Gentamicin: Multiple daily dose (MDD) regimen, 2 mg/kg load, then 1.7 mg/kg IV q8h, or once-daily dose (OD) regimen, 5-7 mg/kg IV q24h (assuming normal renal function)
- Imipenem/cilastatin: 500 mg IV q6h
- Meropenem: 1 g IV q8h
- Metronidazole: 1 g (15 mg/kg) IV load then 500 mg IV q8h or 500 mg PO q8h
- Piperacillin/tazobactam: 3.375 g IV q6h or 4.5 g IV q8h
- Ticarcillin/clavulanate: 3.1 g IV q6h
- Trimethoprim/sulfamethoxazole DS: 1 tablet PO BID
- Trovafloxacin: 300 mg IV for 1st dose, then 200 mg IV/PO daily
First Line
- Uncomplicated diverticulitis (outpatient), 10-14 days
- Amoxicillin-clavulanate 875/125 mg PO BID
- Trimethoprim/sulfamethoxazole DS 1 tablet PO BID AND metronidazole 500 mg PO q6h
- Ciprofloxacin 500 mg PO BID AND metronidazole 500 mg PO q8h
- For patients intolerant of metronidazole, consider clindamycin
- Complicated diverticulitis
- Ticarcillin/clavulanate: 3.1 g IV q6h or
- Ampicillin/sulbactam: 3 g IV q6h or
- Ceftriaxone 1 g IV q24h AND metronidazole 500 mg IV q8h
- Levofloxacin 500 mg or 750 mg IV q24h (or ciprofloxacin 400 mg IV q12h) AND metronidazole 1 g IV q12h
- Imipenem 500 mg IV q6h or meropenem 1 g IV q8h
Follow-Up
Disposition
Admission Criteria
- Intractable pain and/or vomiting
- High fever
- Peritonitis
- Failure to respond to outpatient management
- Severe disease on CT scan
- Significant leukocytosis
- Immunocompromised or steroid-dependent patients
- Recurrent episodes
- Comorbidities: Renal insufficiency, liver dysfunction, COPD, diabetes with end-organ damage
- Extremes of age
- Uncertainty of diagnosis
Discharge Criteria
- Mild cases (low-grade fever, mild discomfort) of known diverticular disease
- Minimal comorbidities
- Tolerating PO
Issues for Referral
Massive diverticular bleeding requiring GI or surgical consultation
Follow-Up Recommendations
- Clear liquids
- Clinical improvement should be seen in 3 days, after which diet can be advanced
- Advise patients to call for increasing pain, fever, or inability to tolerate PO
- Colonoscopy (or contrast enema x-ray with flexible sigmoidoscopy) should be obtained after resolution of initial episode
- Patients do NOT need to avoid seeds and nuts
Pearls and Pitfalls
- CT scanning differentiates diverticulitis as complicated or uncomplicated:
- Surgery reserved for complicated cases, but nonoperative management becoming more prevalent
- Most cases of uncomplicated diverticulitis rarely progress to complicated disease
- Multiple attacks do not seem to lead to increased complications.
- Diverticulitis does not seem to be a progressively worsening process
- Acute episodes can present at any stage.
- Severe disease on initial CT scan
- Increased risk of failure of medical therapy
- High risk of secondary complications
Additional Reading
- Lorimer JW, Doumit G. Comorbidity is a major determinant of severity in acute diverticulitis. Am J Surg. 2007;193:681-685.
- Nelson RS, Ewing BM, Wengert TJ, et al. Clinical outcomes of complicated diverticulitis managed nonoperatively. Am J Surg. 2008;196(6):969-972.
- Rafferty J, Shellito P, Hyman NH, et al.; Standards Committee of American Society of Colon and Rectal Surgeons. Practice parameters for sigmoid diverticulitis. Dis Colon Rectum. 2006;49:939-944.
- Stollman NH, Raskin JB. Diagnosis and management of diverticular disease of the colon in adults. Ad Hoc Practice Parameters Committee of the American College of Gastroenterology. Am J Gastroenterol. 1999;94:3110-3121.
- Touzios JG, Dozois EJ. Diverticulosis and acute diverticulitis. Gastroenterol Clin North Am. 2009;38(3):513-525.
- Yoo PS, Garg R, Salamone LF, et al. Medical comorbidities predict the need for colectomy for complicated and recurrent diverticulitis. Am J Surg. 2008;196:710-714.
See Also (Topic, Algorithm, Electronic Media Element)
Diverticulosis
Codes
ICD9
- 562.11 Diverticulitis of colon (without mention of hemorrhage)
- 562.13 Diverticulitis of colon with hemorrhage
ICD10
- K57.20 Diverticulitis of large intestine with perforation and abscess without bleeding
- K57.32 Diverticulitis of large intestine without perforation or abscess without bleeding
- K57.92 Diverticulitis of intestine, part unspecified, without perforation or abscess without bleeding
- K57.21 Diverticulitis of large intestine with perforation and abscess with bleeding
- K57.2 Diverticulitis of large intestine with perforation and abscess
- K57.33 Diverticulitis of large intestine without perforation or abscess with bleeding
- K57.80 Diverticulitis of intestine, part unspecified, with perforation and abscess without bleeding
- K57.81 Diverticulitis of intestine, part unspecified, with perforation and abscess with bleeding
- K57.8 Diverticulitis of intestine, part unspecified, with perforation and abscess
SNOMED
- 307496006 Diverticulitis (disorder)
- 4494009 Diverticulitis of large intestine
- 235774002 Colonic diverticular abscess (disorder)
- 76953007 Diverticulitis of colon with perforation (disorder)
- 430347001 Diverticulitis of cecum (disorder)
- 430877000 Diverticulitis of rectum (disorder)