| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Clinical Observations |
1 Department of Radiology, Hospital of the University of Pennsylvania, 3400
Spruce St., Philadelphia, PA 19104.
2 Department of Pathology, Hospital of the University of Pennsylvania,
Philadelphia, PA.
Received December 27, 2007;
accepted after revision February 29, 2008.
Address correspondence to M. S. Levine
(marc.levine{at}uphs.upenn.edu).
Abstract
 Top Abstract IntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
CONCLUSION. Chronic diverticulitis is a distinct pathologic entity characterized by the frequent development of chronic obstructive symptoms and abdominal pain rather than the classic clinical findings of acute sigmoid diverticulitis. Barium enema examinations usually reveal a relatively long segment of circumferential narrowing in the sigmoid colon with a spiculated contour and tapered margins, sometimes associated with retrograde obstruction. Our experience suggests that chronic diverticulitis can often be diagnosed on the basis of the characteristic clinical and radiographic findings in these patients.
Keywords: abdominal CT • barium enema • chronic diverticulitis • gastrointestinal imaging
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
In our practice, however, we have encountered a subset of patients with a chronic form of diverticulitis who presented with obstructive symptoms or abdominal pain of at least 2 months duration, often in the absence of abdominal tenderness, fever, or leukocytosis. At surgery, however, these patients had pathologic findings of diverticulitis with acute or chronic inflammatory changes and associated fibrosis. Because of its differing clinical presentation, chronic diverticulitis poses a diagnostic challenge for clinicians caring for these patients. Although CT is the imaging technique of choice for the detection of acute diverticulitis [4–6], patients with chronic diverticulitis may undergo a barium enema examination as the initial diagnostic imaging test because of chronic obstructive symptoms or abdominal pain. To our knowledge, this condition has not been described previously in the radiologic literature. The purpose of our study therefore is to present a series of patients with chronic diverticulitis on barium enema examinations and to correlate the radiographic findings with the clinical and pathologic findings in these patients.
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
Seven patients were men (50%) and seven were women (50%). The mean age was 64 years (age range, 33–84 years). Medical records for these 14 patients were reviewed by one author to determine the clinical presentation (including the nature and duration of clinical signs and symptoms) and treatment (Table 1).
|
Examination Technique
All 14 patients underwent barium enema examinations (with spot images and
overhead radiographs), including eight double-contrast barium enemas (57%) and
six single-contrast barium enemas (43%). All studies were performed using
digital fluoroscopic equipment (Diagnost 76, Philips Healthcare or Sireskop
SD, Siemens Medical Solutions). All of the studies were performed by
residents, fellows, or one of three attending gastrointestinal radiologists,
and all were interpreted and reported by the attending radiologists. In three
patients who had repeat barium enemas, the initial examination was analyzed
for this study. All patients received 1 mg of IV glucagon at the outset of the
procedure to decrease patient discomfort and minimize colonic spasm.
Ten (71%) of the 14 patients also underwent abdominal CT within 6 months of the barium enema examinations. All 14 patients underwent helical CT of the abdomen (HiSpeed Advantage or HiSpeed CT/I, GE Healthcare) according to an established protocol. All but one patient received 500 mL of oral contrast material (2–3% diatrizoate meglumine and diatrizoate sodium solution [Gastrografin, Bracco]) and 150 mL of IV contrast material (diatrizoate meglumine [Hypaque, Sanofi-Aventis] or iohexol [Omnipaque 300, GE Healthcare]). CT images were routinely obtained during the portal venous phase with the patient in a supine position during suspended respiration. Axial images were obtained at 5- or 7-mm slice collimations (pitch, 1.3:1; 200–220 mAs) and reconstructed with a soft-tissue algorithm. The CT examinations were performed before the barium enema examinations in six patients (mean interval, 1.4 months; range, 0.1–3.8 months) and after the barium enema examinations in four patients (mean interval, 1.6 months; range, 0.1–5.6 months). We included CT examinations performed up to 6 months before or after the barium enema examinations because of the chronic nature of the disease and long duration of symptoms in these patients. CT examinations were not included, however, if surgery had been performed between the two studies.
Review of Images
All of the images from the 14 barium enema examinations and 10 abdominal CT
examinations were reviewed by a consensus of two authors (both
gastrointestinal radiologists with 25 and 23 years of experience) to determine
the radiographic findings associated with chronic diverticulitis, including
the appearance, length and width (magnification was accounted for on the
radiographs by using the approximate height of lumbar vertebral bodies as a
reference standard), and location of the diseased segment.
The barium enema findings were reviewed to determine the presence or absence of colonic obstruction, focal extravasation into a pericolic collection, or fistula formation. The presence and location of underlying colonic diverticulosis were also assessed. On review of the CT images, the presence or absence of localized wall thickening (> 5 mm) [5, 6], pericolic fat stranding, fistulas, giant diverticula, small-bowel or colonic obstruction, small-bowel dilatation, pneumoperitoneum, and portomesenteric venous gas was noted. There were no major discrepancies between the original radiographic reports and the retrospective review of the barium enema examinations or abdominal CT examinations.
Review of Pathologic Findings
Histologic sections from the resected surgical specimens in these 14
patients were reviewed retrospectively by two authors (both pathologists) to
characterize the pathologic findings of chronic diverticulitis, including the
presence of diverticular disease, inflammation, and fat stranding.
Inflammation was defined by the presence of acute inflammatory cells (i.e.,
neutrophils) or chronic inflammatory cells (i.e., lymphocytes) in the bowel
wall or adjacent pericolic fat or within pericolic collections. Fat stranding
was defined as fibrosis in the pericolic fat on representative pathologic
specimens.
|
|
|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
Twelve patients (86%) had prior episodes of diverticulitis (mean number of episodes, 1.7; range, 1–4), and six (43%) had received antibiotics before surgery without clinical improvement. The indications for surgery (sigmoid resection) in these 14 patients included colonic luminal narrowing or obstruction (or both) on barium enema examinations in seven patients (50%) (six of whom also had intractable obstructive symptoms and one of whom also had an obstructing stricture at colonoscopy); symptomatic, intractable fistulas in three (21%); recurrent diverticulitis in two (14%); failed medical treatment for diverticulitis in one (7%); and a giant sigmoid diverticulum in one (7%). Only one (7%) of the 14 patients (described previously) underwent preoperative colonoscopy.
|
|
All 14 patients had findings of sigmoid diverticulitis on barium enema examinations. There was circumferential narrowing of the sigmoid colon in thirteen patients (93%) (Figs. 1, 2A, 2B, 3A, 3B, 4, 5, and 6). The mean length of the narrowed segment was 4.8 cm (range, 2–6 cm) and the mean width (at its narrowest point) was 0.6 cm (range, 0.1–1.7 cm). The segment of narrowing in all 14 patients had a tethered or spiculated contour with distorted but preserved mucosal folds (Figs. 1, 2A, 2B, 3A, 3B, 4, 5, and 6).
|
|
|
The remaining patient had findings of sigmoid diverticulitis with asymmetric mass effect, spiculation and tethering of the contour, and distorted mucosal folds but no evidence of circumferential colonic narrowing (Fig. 7A).
|
Abdominal CT—Abdominal CT revealed findings of sigmoid diverticulitis in nine (90%) of the 10 patients who underwent CT. The mean length of involved colon was 8.9 cm (range, 4–15 cm). Localized wall thickening (mean thickness, 12.5 mm; range, 8–19 mm) and pericolic fat stranding were present in all nine of these patients (Figs. 2B and 3B). Inflammatory collections were identified in three patients (30%) (Fig. 7B) and fistulas in three (30%), including one colocolic fistula and two colovesical fistulas. One of the colovesical fistulas was seen in the patient with fecaluria and pneumaturia. The other two fistulas suggested on CT were found in patients without barium enema or clinical findings of fistulas. One patient was found to have a 7 x 5 cm giant sigmoid diverticulum. None of the CT scans revealed small-bowel dilatation or obstruction, pneumoperitoneum, or portomesenteric venous gas, and none of the three patients with colonic obstruction findings on barium enema examinations were found to have definite colonic obstruction on CT.
|
Finally, one patient with acute and chronic inflammation of the sigmoid colon had an associated diverticular abscess. Thus, all 14 patients had pathologic findings of chronic diverticulitis with chronic inflammatory cells or fibrosis of the pericolic fat, and 11 (79%) of these 14 patients also had acute inflammatory changes in the sigmoid colon.
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
As the name implies, chronic diverticulitis is a variant of diverticulitis in which symptoms can persist for 6 months to 1 year or longer [8]. In our study, the mean duration of symptoms at the time of presentation was 11 months, and one patient had symptoms for as long as 3 years. In contrast, patients with acute divert iculitis have a mean duration of symptoms of only 2–14 days [9–12]. Chronic diverticulitis therefore is characterized by a far more indolent course and longer duration of clinical signs and symptoms than the acute form of this disease.
Chronic diverticulitis can also be distinguished from acute diverticulitis by the nature of the presenting signs and symptoms. Whereas patients with acute diverticulitis usually have a combination of left lower quadrant pain, tenderness, leukocytosis, and fever [2, 3], only nine (57%) of our 14 patients with chronic diverticulitis had left lower quadrant abdominal pain (the mean duration of pain was 11 months), and these patients rarely if ever had abdominal tenderness, rebound, guarding, fever, or leukocytosis. Instead, 10 (71%) of our 14 patients with chronic diverticulitis had one or more signs or symptoms of colonic obstruction, including constipation, decreased stool caliber, nausea and vomiting, and bloating. This compares with a prevalence of obstructive symptoms of only 6.5% in a recent series of surgical patients with acute sigmoid diverticulitis [13]. Patients with chronic diverticulitis therefore are much more likely to have obstructive symptoms than those with acute diverticulitis.
Because of chronic obstructive symptoms and abdominal pain in our patients with chronic diverticulitis, they were more likely to undergo barium enema examinations than those with acute diverticulitis in whom abdominal CT is almost always performed as the initial diagnostic imaging test. In our study, barium enema examinations were performed before or instead of CT in eight (57%) of 14 patients with chronic diverticulitis. In 13 patients (94%), the barium enema findings revealed a relatively long segment of circumferential narrowing in the sigmoid colon with a spiculated contour and generally tapered margins, sometimes associated with retrograde obstruction (Figs. 1, 2A, 2B, 3A, 3B, 4, 5, and 6). In contrast, acute diverticulitis is more likely to be characterized on barium enema examinations by asymmetric mass effect and tethering of the sigmoid colon due to an inflammatory collection abutting the bowel without circumferential luminal narrowing. Chronic diverticulitis therefore produces characteristic findings on barium enema examinations that can usually be differentiated from those of acute diverticulitis in the proper clinical setting.
The circumferential luminal narrowing in chronic diverticulitis is presumably caused by chronic inflammation or fibrosis of the colonic wall and surrounding pericolic fat, as was observed on the resected pathologic specimens in all 14 patients (100%) in our study. In pathology texts, chronic diverticulitis is characterized by longitudinal spread of the inflammatory process in the colonic wall, progressively ensheathed by inflammatory and fibrous tissue [14, 15]. These pathologic features most likely account for the greater length of the narrowed segment and the higher frequency of circumferential narrowing in chronic diverticulitis than in acute diverticulitis. Nevertheless, 11 patients (79%) also had acute inflammatory cells in the sigmoid colon and one (7%) had a diverticular abscess. It therefore is uncertain how often chronic diverticulitis results from recurrent episodes of acute diverticulitis superimposed on low-grade, smoldering disease. Whatever the explanation, the high prevalence of obstructive symptoms in patients with chronic diverticulitis can be attributed to the high frequency of circumferential narrowing of the sigmoid colon in these individuals.
The major consideration in the differential diagnosis of chronic diverticulitis with narrowing and spiculation of the sigmoid colon on barium enema examinations is metastatic disease, resulting from intraperitoneal seeding or direct extension of a contiguous pelvic malignancy. However, patients with metastatic tumor often have known primary malignancies, more rapid progression of symptoms, and associated weight loss, whereas our patients with chronic diverticulitis usually had chronic obstructive symptoms without associated weight loss or known malignant tumors. Endometriosis may occasionally be manifested on barium enema examinations by circumferential narrowing and spiculation of the sigmoid colon, but this condition usually occurs in young women with cyclic abdominal symptoms rather than older patients.
Primary colonic carcinoma is also a frequent cause of sigmoid narrowing in older patients, but mucosal folds are usually obliterated within the narrowed segment, which has abrupt, shelflike borders. Although colonic carcinoma can usually be differentiated from diverticulitis on the basis of the radiographic findings, tumors that spread submucosally or perforate with associated pericolic inflammation can sometimes mimic the appearance of diverticulitis. It can also be more difficult to distinguish malignant tumor from diverticulitis in patients with relatively high-grade obstruction that prevents adequate visualization of the narrowed segment, precluding analysis of its radiographic features. In most cases, however, the diagnosis of chronic diverticulitis can be suggested on the basis of the clinical and radiographic findings in these patients.
CT revealed findings of sigmoid diverticulitis with localized wall thickening and pericolic fat stranding in nine (90%) of 10 patients in whom CT was performed (Figs. 2B and 3B). CT also revealed inflammatory collections in three patients (Fig. 7B) and fistulas in three, but no patients had definite evidence of obstruction on CT. Unlike the findings on barium enema examinations, the CT findings in patients with chronic diverticulitis therefore were similar to those in patients with acute diverticulitis [5, 6].
Because of the circumferential luminal narrowing that was observed in most of our patients with chronic diverticulitis, surgical resection of the sigmoid colon was required for relief of obstructive symptoms. In contrast, stricture formation and obstruction have necessitated surgical intervention in only 6–12% of patients treated for acute diverticulitis [16, 17]. Our experience therefore suggests that patients with chronic diverticulitis are more likely to require surgical resection of the diseased sigmoid colon than those with the acute form of this disease.
Most patients with acute diverticulitis are treated medically. Thus, endoscopy and biopsy are required to rule out colonic carcinoma whenever the radiographic findings are equivocal for diverticulitis versus tumor. In contrast, patients with chronic diverticulitis are more likely to undergo surgery because of varying degrees of colonic obstruction. Endoscopic visualization and biopsy of the diseased segment become less important in this group because histologic examination of the resected specimen will enable a definitive pathologic diagnosis to be made in almost all cases. In our study, only one (7%) of 14 patients with chronic diverticulitis underwent preoperative colonoscopy.
Our investigation has the limitations of a retrospective study, including selection bias and interpretation bias. Our requirement of pathologic confirmation of diverticulitis on surgical specimens created a particular selection bias because patients with circumferential luminal narrowing presumably were more likely to undergo surgery than those with asymmetric disease and no luminal narrowing. Nevertheless, this was a descriptive study of the clinical and radiographic findings in chronic diverticulitis and not an analysis of radiographic accuracy in detecting this condition.
In conclusion, we have reported a small subset of patients with diverticulitis who developed chronic disease with fibrosis and scarring, often leading to the development of luminal narrowing in the sigmoid colon. Most of these patients presented with chronic obstructive symptoms and abdominal pain rather than the classic clinical findings of acute sigmoid diverticulitis. In almost all cases, barium enema examinations revealed a relatively long segment of circumferential narrowing in the sigmoid colon with a spiculated contour and tapered margins, sometimes associated with retrograde obstruction. Our experience suggests that chronic diverticulitis can often be diagnosed on the basis of the characteristic clinical and radiographic findings in these patients.
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
CiteULike 
Complore 
Connotea 
Del.icio.us 
Digg 
Reddit 
Technorati What's this?
This article has been cited by other articles:
|
|
 |
|
  M. S. Levine, S. E. Rubesin, and I. Laufer Barium Studies in Modern Radiology: Do They Have a Role? Radiology, January 1, 2009; 250(1): 18 - 22. [Full Text] [PDF]
|
|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
