Diverticular Disease of the Large Bowel

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Diverticular Disease of the Large Bowel

• Torin P. Fitton, MD
• September 14, 2005

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Epidemiology

• Occurs frequently, particularly among elderly
  patients
• Incidence rises with age
• 33 general population develop it by 45 years of
  age and 66 by 85 years of age
• Rare in patients younger than 40 years of age
  with higher reported morbidity
• Male Female ratio is equal
• Race
• Primarily a disease of Western industrialized
  nations likely related to diet

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Pathogenesis

• More prevalent in countries with low fiber intake
• Colon depends on minimal amount of bulk to propel
  contents towards rectum
• Low bulk increases contractions and pressure
  causing herniation
• Herniation usually at entry of arteriae rectae
  along mesentery and lateral tenia
• Involve mucosa covered by serosa

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Pathology

• Usually multiple
• Much more common in left colon than right colon
• 90 occur in sigmoid
• Much more likely to be right-sided if occurs in
  Asian patient
• Colonic wall is thickened due to hypertrophy of
  muscle layer

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Clinical Presentation

• Most patients are asymptomatic unless a
  complication develops
• Morbidity and mortality of diverticula are
  related to complications which include
  inflammation and bleeding
• Occur in 10-20 of patients with diverticulosis
  during their lifetimes

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Diverticulitis

• Abscess or peridiverticular inflammation
  initiated by the rupture of a microscopic mucosal
  abscess into the mesentery or peritoneal cavity
• Presents as LLQ pain, fever, chills and
  obstipation or diarrhea
• To contain the inflammation, nearby viscera
  migrate toward diverticulitis which include
  omentum, small bowel, bladder, uterus, fallopian
  tubes and vagina
• Infection may progress, spontaneously resolve,
  fistulize, or obstruct

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Hemorrhage

• Lower GI Hemorrhage
• Results from rupture of small blood vessels that
  are stretched while coursing over the dome of the
  diverticula
• Sudden, painless with urge to defecate
• Bright-red or wine colored
• Amount is often massive and tends to stop
  spontaneously

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Evaluation and Management

• Initial evaluation to include history physical
  examination
• Abdominal pain steady, severe, deep
• Fever common
• History of previous episodes, altered bowel
  habits
• Pneumaturia, recurrent UTI, feculent vaginal
  discharge
• Obvious peritonitis

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Laboratory Studies

• Complete blood count leukocytosis and/or a left
  shift in acute diverticulitis
• 60 of patients may have a normal white blood
  cell count, particularly elderly and
  immunocompromised patients.
• Type and cross-match/coagulation profiles in
  patients with lower GI bleeding or frank
  peritonitis.
• Urinalysis/urine culture identifies infections,
  hematuria colovesicular fistulas
• Lipase/amylase/LFTs Establish other etiologies
  particularly important when patients present
  atypically (eg, steroid therapy, elderly
  patients, those with diabetes) or relatively late
  in the course of an inflammatory process with
  generalized tenderness or frank peritonitis.

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Radiographic Imaging

• Plain radiographs identifies signs of intestinal
  irritation (ileus) and two thirds of visceral
  perforations (free air). Identify volvulus, bowel
  obstruction, renal stones, and occasionally
  intraabdominal masses.
• Ultrasonography less sensitive and specific than
  other modalities less readily available, and
  reliability is operator dependent.
• Endoscopy Useful to diagnose diverticular
  disease and to establish the source of lower GI
  bleeding but is avoided in acute diverticulitis
  because of the fear of perforation and
  peritonitis.

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Computed Tomography

• Test of choice for acute diverticulitis
  diverticula, localized colonic wall thickening
  (gt5 mm), abscesses, fistulas, and pericolic fat
  inflammation and exclude other pathologies.
• Prognostic as well as the presence of abscesses,
  extraluminal air, or extravasation of contrast
  media is highly predictable of failure of medical
  treatment

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Management

• IV Fluid Resuscitation
• Invasive Monitoring if necessary
• NPO
• IV Antibiotics with Gram and anaerobic coverage
• Percutaneous drainage
• In majority of patients, diverticulitis will
  resolve with antibiotics alone

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Indications for Surgery

• Peritonitis
• Closed loop obstruction secondary to bowel
  adherence
• Recurrent episodes of acute uncomplicated
  diverticulitis
• Emergency Surgery
• 7 mortality Hartmann procedure
• 9 mortality Fecal peritonitis
• 35 mortality Generalized peritonitis

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Surgical Considerations

• Clearing of infection and bowel preparation are
  goals before a resection should be attempted in 1
  stage
• If persistent soilage, needs sigmoidectomy with
  colostomy and closure of rectal stump (Hartmann
  procedure)
• Reversal 8-12 weeks later
• Extent of colonic resection is very important
• Anastomoses after resection for diverticulitis
  have a high incidence of complication
• Ischemia secondary to tension from inadequate
  mobilization
• Inclusion of diverticulum in anastomosis

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A Word About Fistulas

• Most common cause of fistulas is diverticulitis
  in absence of tumor or Crohns disease
• Indolent subacute diverticulitis may resolve by
  releasing into neighboring viscus resulting in
  fistula
• Most common colovesical (48) colovaginal
  (44) colocutaneous (4) colotubal (2) and
  coloenteric (2)