Diverticulitis acute colonic

Traditionally,contrast enemahasbeen the mainstayin the evaluation of patients suspected of having diverticulosis or acute colonic diverticulitis (Fig. 3.1). 

Acute colonic diverticulitis is a common cause of acute abdominal symptoms, especially in elderly patients. In turn, diverticulitis develops in 10-25% of the population vyith diverticulosis (Roberts et al. 1995). It is, in virtually all cases, the result of a micro-perforation of a single diverticulum (Fig. 3.5). 

The clinical diagnosis and assessment of acute colonic diverticulitis can be difficult (Chappuis and Cohn 1988). The classic pattern of left lower quadrant pain, tenderness, fever, and leukocytosis is suggestive of acute colonic diverticulitis but can be mimicked by numerous acute abdominal conditions. Symptoms such as nausea, vomiting, constipation or diarrhoea lead to a high rate of wrong diagnosis up to 34% of cases. 

Brengman ML, Otchy DP (1998) Timing of computed tomography in acute diverticulitis. Dis Colon Rectum 41 1023-1028... 

Chappuis CW, Cohn I (1988) Acute colonic diverticulitis. Surg Clin North Am 68 301-313... 

Wada M, Kikuchi Y, Doy M (1990) Uncomplicated acute diverticulitis of the cecum and ascending colon. Sonographic findings in 18 patients. Am J Roentgenol 155 283-287... 

Diverticulosis can also be diagnosed by endoscopy (Fig. 3.2) however, when diverticulits is suspected clinically, endoscopy is contraindicated. After the acute phase of inflammation, the colon should be examined to exclude a colon carcinoma. So a complete colonic evaluation should generally be performed 6-8 weeks after the resolution of a diverticulitis. In cases of inflammation, coloscopy is often incomplete and painful for the patient. The risk for perforation is also higher because of the air insufflation. 

At most hospitals, CT has replaced barium enema examination of the colon for diagnosis of suspected diverticulitis. Compared with sonography, the operator dependency is less (Ambrosetti et al. 1997). One of the reasons is that diverticulitis is primarily an extramural process, and barium enema diagnosis depends on the secondary effects on the barium column caused by the extramucosal manifestations of acute inflammation. 

The differential diagnosis of acute diverticulitis is wide (Gritzmann et al. 2002). One important reason for left lower quadrant pain can be a torsion or necrosis of appendices epiploicae of the left colon. A well-defined point of pain is typical, and is the effect of a local peritonitis. 

Any form of colitis, such as pseudomembranous, acute ulcerative colitis or Crohn s colitis can also mimic diverticulitis. Usually, pseudomembranous colitis is associated with antibiotic therapy. In most cases a significant thickening of the colon is found. 

Ambrosetti P, Grossholz M, Becker C et al (1997) Computed tomography in acute left colonic diverticulitis. Br J Surg 84 532-534... 

Fig. 17.16 Sigmoid diverticulitis. Multiple air-containing diverticula are found along the sigmoid colon. In this patient with acute pelvic pain, focal wall thickening, stenosis, and paracolic fat stranding (arrow) are signs of acute diverticulitis involving the distal sigmoid colon. R, rectum...

Labs JD, Sarr MG, Fishman EK et al (1988) Complications of acute diverticulitis of the colon improved early diagnosis with computerized tomography. Am J Surg 155 331-336... 

The contraindications to CTC are few and, in general, different than these encountered with conventional colonoscopy (Rex et al. 1987). Weight and girth limitations of the scanner, artifacts from metal prosthesis and claustrophobia are examples of contraindications unique to CT. Absolute contraindications to instrumentation of the colon include presence of an acute abdomen, recent abdominal or pelvic surgery, colonic hernia, and acute diverticulitis (Fig. 2.3). Relative contra-indications include pregnant patients, patients with hip replacements, claustrophobia and an incompetent ileocecal valve (Fig. 2.4). 

A patient with an acute abdomen should not he inflated with room air or CO2, and a consultation with a surgeon is most appropriate. Patients with active diverticulitis should not he referred to CT colonography. If an abscess or free air is suspected, a CT of the abdomen and pelvis can be performed with oral and IV contrast. Insufflation of the colon is contraindicated and may cause perforation and widespread peritonitis. Similarly, if a patient has recently undergone pelvic or abdominal surgery. 

Presently, CT colonography has no role in the diagnosis of acute diverticulitis, and, in addition, the distension of the colon may lead to perforation. In selected cases, CTC may help in the differential diagnosis between diverticulitis and cancer after the acute inflammatory episode has subsided. 

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