Diverticulitis                    REF: diverticulitis 2007

William V. Harford, Jr., M.D.
University of Texas Southwestern Medical Center

Definition/Key Clinical Features
Differential Diagnosis
Best Tests
Best Therapy
Best References

Definition

• Inflammation of diverticula
  • Small herniations of colonic mucosa and submucosa through the muscularis propria
  • Occurs in 10%–25% of patients with known diverticulosis

Key Clinical Features

• Abdominal pain and localized tenderness, usually in left lower quadrant
• Anorexia
• Nausea without vomiting
• Diarrhea or constipation caused by colonic inflammation
• Low-grade fever
• Complications
  • Phlegmon
  • Abscess
  • Perforation
  • Bacteremia
  • Sepsis syndrome
  • Fistula formation

Differential Diagnosis

General Population

• Appendicitis
• Mesenteric adenitis
• Crohn disease
• Meckel diverticulitis
• Infectious colitis or ileitis
• Small-bowel obstruction
• Perforated peptic ulcer
• Acute cholecystitis
• Acute pancreatitis
• Urinary tract infection

Women of Childbearing Age

• PID
• Rupture of ovarian follicle or cyst
• Ruptured ectopic pregnancy
• Ovarian torsion

Middle-Aged to Elderly Patients

• Ischemic colitis
• Perforated cancer of right colon

Young Children

• Intussusception

Best Tests

• If symptoms are mild and respond to empiric therapy, defer x-rays
• History and physical exam are often sufficient for a presumptive diagnosis
• In women of childbearing age, perform pelvic and abdominal ultrasound
• Plain abdominal x-ray to exclude other abdominal conditions
• If symptoms are severe, perform the following
  • Plain abdominal x-ray to exclude abdominal obstruction or perforated bowel
  • Abdominal CT with oral and I.V. contrast
• After acute symptoms have resolved, consider colonoscopy or BE to exclude cancer and inflammatory bowel disease

Best Therapy

• For mild symptoms, recommend liquid diet or low-roughage diet
• If symptoms are severe or if there is concern for intra-abdominal infection, get surgical consultation
• Antibiotic therapy
• High-fiber diet may be useful for prevention

Antibiotic Therapy for Diverticulitis

Amoxicillin-clavulanate

• For mild diverticulitis
• Comparable efficacy
• Dose: 875/125 mg p.p. q. 12 hr
• Cost/mo: $214.98

Sulfamethoxazole-trimethoprim + Metronidazole

• For mild diverticulitis
• Comparable efficacy
• Dose: 1 double-strength S/T b.i.d. + 500 mg metronidazole p.o. q. 8 hr
• Cost/mo: $19.49 + $27.99

Ciprofloxacin + Metronidazole

• For mild diverticulitis
• Comparable efficacy
• Dose: 500 mg ciprofloxacin p.o. q. 12 hr + 500 mg metronidazole P.O. q. 8 h
• Cost/Mo: $444.97 + $27.99

Ampicillin-sulbactam

• For severe/complicated diverticulitis
• Comparable efficacy
• Dose: 1.5–3.0 g I.V. q. 6 hr

Cephalosporin Alone

• For severe/complicated diverticulitis
• Comparable efficacy
• Cefotetan
  • Dose: 2 g I.V. q. 12 hr
• Cefoxetin
  • Dose: 2 g I.V. q. 6 h

Cefotetan + Gentamicin

• For severe/complicated diverticulitis
• Comparable efficacy
• Dose: 1 g cefotetan q. 12 hr (or 400–900 mg clindamycin q. 8 hr for penicillin-allergic patients) + 5–7.5 mg/kg gentamicin in single daily dose

Metronidazole + Ceftriaxone

• Comparable efficacy
• Dose: 500 mg metronidazole I.V. q. 6 hr + 1 g ceftriaxone I.V. q. 24 hr

Best References

The American Society of Colon and Rectal Surgeons: Dis Colon Rectum 43:289, 2000

Stollman, et al: Am J Gastroenterol 94:3110, 1999

Society for Surgery of the Alimentary Tract: J Gastrointest Surg 3:212, 1999

July 2004