Ambrosetti et al. reported on 423 patients with acute diverticulitis on CT scan, categorizing them as

having either moderate disease or severe disease. Criteria for moderate disease included localized wall

thickening or inflammation of pericolic fat (modified Hinchey stage Ia; see Table 69-2). Severe disease

included the presence of extraluminal air or contrast (contained perforation) or abscess (modified

Hinchey stages Ib and II). Of the 42 patients who failed nonoperative management, 32 had severe

disease. Twenty percent of those patients who were initially successfully managed nonoperatively

developed secondary complications such as fistulas (median follow-up 46 months). They concluded that

the presence of severe disease at the index episode predicted failure of nonoperative management and

that there is a high risk of secondary complications after initial nonoperative management.56

Ultrasound. Abdominal ultrasound has been emphasized in the European literature and is attractive as

a strategy for limiting radiation exposure. However, its diagnostic limitations (user dependence,

interference from overlying bowel gas, and decreased accuracy in obese patients) have precluded its

widespread adoption in the United States. In skilled hands, it may have a role in image-guided

percutaneous drainage of abscesses.57

Contrast Enema Study (Barium Enema). Contrast enemas have been the “gold standard” test for the

presence and anatomic distribution of diverticula (Fig. 69-7). For reasons cited earlier, CT scan has

supplanted contrast enemas in the acute setting. However, they are better than CT for helping

distinguish colon cancer from diverticular obstruction, and contrast can also traverse narrowed areas of

the colon impassable by an endoscope. While caution must be used in the acute setting to avoid

perforation, these studies can be performed safely. Caveats are that contrast must be administered

gently, water-soluble contrast should be used, and a single contrast study is performed in unprepared

bowel to avoid the increased risk of perforation and fecal contamination with the administration of air.

In chronic DD, the contrast enema can demonstrate stricture, angulation, and segmentation-type

contractions. It can also be useful for the evaluation of fistulas.

Figure 69-7. Barium enema showing multiple diverticula of the colon.

6 Endoscopy. Like contrast enema studies, colonoscopy or flexible sigmoidoscopy can be used

judiciously in the acute setting. It is particularly helpful in distinguishing malignancy from DD and can

therefore help guide early management of acute presentations when malignancy as the cause of

symptoms is being considered.

Cystoscopy. Cystoscopy can help diagnose colovesical fistulas. Although the fistula tract is usually

difficult to see, focal hyperemia and inflammation may be noted. Symptoms of a colovesical fistula and

air in the uninstrumented bladder on CT scan are usually sufficient for diagnosis.

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TREATMENT

Symptomatic Diverticulosis

Fiber supplements and increased dietary fiber (goal 25 to 30 g/d) constitute the cornerstone of

symptomatic diverticulosis treatment once diverticular stricture has been ruled out as the cause of

symptoms. Stricture is an indication for elective segmental colectomy, typically a sigmoid colectomy to

remove the area of stricture and the most dense region of diverticula.

Hemorrhagic Diverticular Disease

Diverticular hemorrhage stops spontaneously in more than 90% of patients; of these, 75% will not bleed

again.58 Patients who have a second episode of diverticular hemorrhage should undergo hemicolectomy

of the involved portion of colon59 after localizing the site of hemorrhage endoscopically with a tagged

red blood cell scan or with angiography, because these patients are likely to bleed again. If the site of

bleeding cannot be determined definitively as left or right sided, a subtotal colectomy is the procedure

of choice.60

Diverticulitis

7 The treatment of diverticulitis typically parallels the Hinchey classification (Algorithm 69-1)44:

Stage I, confined pericolic abscess: antibiotics and bowel rest

Stage II, pelvic or retroperitoneal abscess: percutaneous abscess drainage

Stage III, purulent peritonitis: resuscitation and urgent operation

Stage IV, feculent peritonitis: resuscitation and urgent operation

Stage I diverticulitis is mild when patients can tolerate a diet, have no systemic symptoms (no fever,

tachycardia, hypotension), and have no substantial peritoneal signs. The CT scan shows either minor

pericolic fat stranding or wall thickening in the presence of diverticulosis. Outpatient management is

usually appropriate for these patients. Broad-spectrum oral antibiotics are prescribed for 7 to 10 days,

and patients start a clear liquid diet, advancing to a solid diet as symptoms resolve. If this is a first

episode of presumed diverticulitis, an elective confirmatory study with either barium enema or

colonoscopy is planned after inflammation has subsided. Progression of symptoms on this regimen

warrants hospital admission and repeat CT scan may be necessary. The vast majority (70% to 100%) of

patients with uncomplicated diverticulitis will recover without operative intervention. Although nearly

a third will relapse, long-term fiber supplementation appears to reduce this risk.61

Severe stage I inflammation is indicated by intolerance of diet, possible nausea and vomiting, fever,

chills, and peritoneal signs on examination, which are often focal. The CT scan may show a phlegmon or

contained pericolic abscess. These patients are admitted to the hospital for parenteral broad-spectrum

antibiotics. They are placed on bowel rest, intravenous fluids are administered, and if nausea and

vomiting are major symptoms, a nasogastric tube may be placed. Analgesia is provided but limited to

enable evaluation of symptom progression. In addition, since narcotics are known to cause strong,

nonpropulsive sigmoid colon contractions, their use in patients with diverticulitis should be minimized.

Small (<2 cm) pericolic abscesses may resolve with intravenous antibiotics; larger contained abscesses

will likely require percutaneous drainage with CT (or possibly ultrasound) guidance.61,62 If a smaller

abscess is treated initially with antibiotics only but symptoms fail to improve, percutaneous drainage

should be considered. Progression of symptoms despite percutaneous drainage of an abscess usually

indicates the need for surgery. Historically, 10% to 25% of patients requiring hospitalization for

treatment of diverticulitis will not improve or will worsen with medical management alone; overall,

30% of hospitalized patients will require an operation. Those patients who recover from an initial

episode of complicated diverticulitis (contained perforation or abscess) should be considered for singlestage, elective segmental colectomy after the resolution of acute inflammation.63 As will be discussed

further, minimally invasive surgical techniques are increasingly being used with good outcomes in these

patients.

Patients who fail nonoperative management of diverticulitis or who present with purulent or feculent

peritonitis require operative treatment. The goal of surgery in these patients – especially if they are

toxic, developing multisystem organ failure, or hemodynamically unstable – is to resect the perforation

and make a stoma. This defines a Hartmann procedure, in which the offending segment of colon is

resected, a proximal stoma is constructed, and the distal colon and/or rectum are closed and left in the

pelvis. The distal remaining segment of colon and rectum is referred to as a Hartmann pouch. This

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