Pseudomembranous colitis

Clostridioides difficile infection: history, epidemiology, risk factors, prevention, clinical manifestations, treatment, and future options

SUMMARYClostridioides difficile infection (CDI) is one of the major issues in nosocomial infections. This bacterium is constantly evolving and poses complex challenges for clinicians, often encountered in real-life scenarios. In the face of CDI, we are increasingly equipped with new therapeutic strategies, such as monoclonal antibodies and live biotherapeutic products, which need to be thoroughly understood to fully harness their benefits. Moreover, interesting options are currently under study for the future, including bacteriophages, vaccines, and antibiotic inhibitors. Surveillance and prevention strategies continue to play a pivotal role in limiting the spread of the infection. In this review, we aim to provide the reader with a comprehensive overview of epidemiological aspects, predisposing factors, clinical manifestations, diagnostic tools, and current and future prophylactic and therapeutic options for C. difficile infection.

Imaging of abdominal and pelvic infections in the cancer patient

Infections are the most commonly encountered complications in patients with cancer. The classical signs and symptoms of infections are often not present in this patient population, which makes the diagnosis more challenging. Host factors play a major role in the development and prognosis of infections in cancer patients; these can be related to the underlying type of malignancy (solid organ versus hematological), tumor burden, anatomic obstruction, altered integrity of barriers (skin or mucosa), treatment-related factors (from chemotherapy, radiation treatment, surgery, interventional procedures, and/or medical device placement) and the degree of immunosuppression. This article reviews common, as well as less common, imaging manifestations of infections and their potential mimics in the abdomen and pelvis in cancer patients and discusses their differentiating features, with the role of imaging in various organs in the abdomen and pelvis taking into consideration relevant clinical background information and the main risk factors.

Early diagnosis and antibiotic treatment for fulminant Clostridium difficile infection

In fulminant Clostridium difficile infection (CDI), early diagnosis is important, and early diagnosis could save fulminant CDI patients that do not qualify for surgery due to severe complicating conditions by conservative antibiotic therapy.

An organized approach to imaging of benign cecal pathologies

Unique problems in cecal embryogenesis and cecal pathology can result in characteristic imaging findings. Familiarity with these findings and utilization of an organized approach help to define the cecum's role in acute abdominal symptoms. Clinical symptoms associated with cecal diseases can be diverse and misleading. This pictorial essay should provide a framework for an understanding of anatomical, infectious, and inflammatory cecal diseases. Knowledge of a broad spectrum of cecal pathologies contributing to these disorders and their corresponding imaging findings can help a radiologist define the diagnosis and guide proper management.

Clostridium difficile colitis: CT findings and differential diagnosis

Clostridium difficile infection (CDI) is a severe and potentially deadly infectious colitis whose incidence is dramatically increasing in the last decades, with more virulent strains. CDI should be suspected in case of unexplained diarrhea and abdominal pain in patients with a recent history of antibiotic use and healthcare exposures; diagnosis is based on a combination of clinical and laboratory findings with demonstration of C. difficile toxins by stool test. The advantages of contrast-enhanced computed tomography (CECT) are the noninvasiveness and the ability to evaluate both the colonic wall and the adjacent soft tissues. Considerable overlap exists between the CECT findings of CDI and those of colitis of other origins, such as typhlitis, ischemic colitis, graft-versus-host disease, radiation colitis and inflammatory bowel diseases; however, some features may help distinguish between these conditions. This paper provides a comprehensive overview of the imaging features of Clostridium difficile colitis and its mimics, with a view to assist the radiologist in reaching the correct diagnosis.

2019 update of the WSES guidelines for management of Clostridioides (Clostridium) difficile infection in surgical patients

In the last three decades, Clostridium difficile infection (CDI) has increased in incidence and severity in many countries worldwide. The increase in CDI incidence has been particularly apparent among surgical patients. Therefore, prevention of CDI and optimization of management in the surgical patient are paramount. An international multidisciplinary panel of experts from the World Society of Emergency Surgery (WSES) updated its guidelines for management of CDI in surgical patients according to the most recent available literature. The update includes recent changes introduced in the management of this infection.

WSES guidelines for management of Clostridium difficile infection in surgical patients

In the last two decades there have been dramatic changes in the epidemiology of Clostridium difficile infection (CDI), with increases in incidence and severity of disease in many countries worldwide. The incidence of CDI has also increased in surgical patients. Optimization of management of C difficile, has therefore become increasingly urgent. An international multidisciplinary panel of experts prepared evidenced-based World Society of Emergency Surgery (WSES) guidelines for management of CDI in surgical patients.

Differential Diagnosis of Colonic Strictures: Pictorial Review with Illustrations from Computed Tomography Colonography

Strictures of the colon can lead to significant morbidity requiring surgical management. The etiology of strictures is broad and generally categorized as benign, malignant, or pseudostrictures. Computed tomography (CT) is a crucial imaging modality in the assessment and characterization of colonic pathologies but colonoscopy remains the diagnostic gold standard. However, in the setting of incomplete colonoscopy due to strictures, the imaging features of CT will be relied on. This review will focus on the CT features of different colon pathologies leading to strictures and will be illustrated with images from 10 years of experience with CT colonography at our institutions from 2002-2012 (Hotel Dieu Hospital, Queen's University and Mount Sinai Hospital, University of Toronto).

Ultrasound diagnosis of Clostridium difficile-associated diarrhea

Clostridium difficile colitis is diagnosed using an immunoassay or polymerase chain reaction (PCR) assay for toxins A/B. Since ultrasound is frequently used as a screening test for hospitalized patients suffering from different abdominal morbidities, we searched for sonographic indicators of C. difficile infection (CDI). In a prospective and blinded case-control study, abdominal ultrasound was performed on hospitalized patients for whom stool samples were sent for C. difficile toxin immunoassay. All patients with positive toxin were included as the case group and patients with negative toxin comprised the control group. Sonographic parameters of both groups were compared. Demographic variables of the 67 patients in the toxin-positive group were similar to those of the 71 patients in the toxin-negative group. The sonographic parameters which were found to be associated with CDI included colonic wall thickening, appearing in 61 (91%) patients of the toxin-positive group versus 15 (21%) patients of the toxin-negative group (p < 0.001), and also internal ring (24 versus 0%, p < 0.001), external ring (15 versus 0%, p < 0.001), ascites (24 versus 10%, p < 0.001), and diminution of large bowel content (16 versus 1%, p < 0.001). Bowel wall thickening had high positive and negative predictive values (0.80 and 0.90, respectively), while the other features had only high positive predictive values (0.7-1.0). Abdominal ultrasound may contribute to the diagnosis of C. difficile colitis in patients developing hospital-acquired diarrhea.

Cytomegalovirus enterocolitis in apparently immunocompetent hosts: evaluation of the radiologic findings and clinical features

OBJECTIVE

To describe the clinical and radiologic features of cytomegalovirus (CMV) enterocolitis in apparently immunocompetent hosts.

MATERIALS AND METHODS

Our institutional review board approved this retrospective study, and informed consent was waived. Twelve apparently immunocompetent patients (7 women and 5 men; mean age, 58 years) with pathologically proven CMV enterocolitis were included. Computed tomographic (CT) scans were retrospectively reviewed to determine the extent and the location of mural thickening, maximal mural thickness, enhancement pattern, that is, single-halo, double-halo, and homogeneous patterns, and ascites.

RESULTS

Eight patients had comorbidities potentially affecting the host immune status, whereas 4 patients were apparently healthy before presentation. On CT, all patients showed mural thickening (range, 4-11 mm) involving the colon (n = 8), the small bowel (n = 1), or both (n = 3). Segmental involvement was most common (n = 9 for colon and n = 2 for small bowel), whereas focal involvement of the rectum (n = 1) and diffuse involvement of the entire ileum (n = 1) or the entire small bowel and colon (n = 1) were also noted. Colonic lesions showed variable enhancement patterns, including the single-halo (n = 6), homogeneous (n = 3), and double-halo patterns (n = 2), whereas all small-bowel lesions in 4 patients exhibited a single-ring pattern. Ascites was present in 7 patients. Complications requiring surgery occurred in 3 patients and included refractory bleeding (n = 2) and bowel perforation (n = 1).

CONCLUSIONS

Cytomegalovirus enterocolitis in immunocompetent hosts typically develops in elderly subjects with comorbidities, although it may also affect relatively young and healthy subjects. On CT, it is characterized by mild mural thickening of the small bowel and the colon and frequently shows segmental involvement and a single-halo enhancement pattern.

A description of CT features of Clostridium difficile infection of the small bowel in four patients and a review of literature

Clostridium difficile associated disease is an increasingly common cause of morbidity and mortality. Pseudomembranous colitis following hospital-administered antibiotic treatment is the most common symptomatic manifestation. Small bowel enteritis caused by C. difficile, however, is rarely described. Here, we present a series of four patients with hospital-acquired small bowel enteritis caused by C. difficile, discuss its CT and histopathological features, and review the current literature.

Clinical review of the management of fulminant clostridium difficile infection

BACKGROUND

Clostridium difficile infection (CDI) is a frequent cause of morbidity and mortality among elderly hospitalized patients. A small but increasing number of patients have developed fulminant CDI, and a significant number of these patients require emergency colectomy. In this review, we discuss the risk factors, pathophysiology, diagnosis, and management of fulminant CDI.

DATA SOURCES

A literature search (Medline, Embase, Cochrane Library, Biosis, Science Citation Index, Ovid Journals) was performed from the period between January 1980 and June 2008 using the key words "Clostridium difficile,""pseudomembranous enterocolitis,""colectomy,""acute abdomen,""antibiotic-associated diarrhea," or "fulminant Clostridium difficile colitis." Articles not in English or not related to human subjects were excluded. For this review, we analyzed the articles identified in our original search and those articles cited in the original review articles. No randomized trials were found on the surgical management of fulminant CDI and only retrospective studies with a minimum of five patients were used in the review. With respect to medical treatment, we based our review on guideline articles, systematic reviews, and available randomized trials.

CONCLUSION

Both the incidence and severity of CDI are increasing. Fulminant CDI is underappreciated as a life-threatening disease because of a lack of awareness of its severity and its nonspecific clinical syndrome. Early diagnosis and treatment are essential for a good outcome, and early surgical intervention should be used in patients who are unresponsive to medical therapy. The surgical procedure of choice is a total abdominal colectomy with end ileostomy, although the mortality rate remains high.

Pediatric hematopoietic stem cell transplantation and the role of imaging

The use of hematopoietic stem cell transplantation (HSCT) in the treatment of children afflicted with many potentially fatal malignant and nonmalignant diseases is well recognized. Although outcomes continue to improve and the utility of HSCT is increasing, HSCT remains a complicated process necessitating support from many medical disciplines, including radiology. Importantly, children who undergo HSCT are at risk for the development of specific complications that are linked to the timeline of transplantation, as well as to the relationship between the underlying diagnoses, severe immune deficiency, cytoreductive regimen, and graft-versus-host reactions. An understanding of the complex interplay of the immune status, therapeutic regimen, and disease allows increased diagnostic accuracy. Successful treatment of these high-risk children requires that radiologists who are involved with their care be familiar with broad concepts, as well as with specific problems that frequently occur following HSCT. In this article, the clinical aspects of pediatric HSCT are summarized, including common complications, and imaging features of these complications are described.

CT of gastrointestinal complications associated with hematopoietic stem cell transplantation

OBJECTIVE

This article illustrates the characteristic CT findings of bowel damage related to drug toxicity, conditioning regimen, infections, and graft-versus-host disease (GVHD) in patients after hematopoietic stem cell transplantation.

CONCLUSION

Although some overlap exists in the CT appearances of the different causes of bowel wall inflammation, the findings are frequently unique enough to suggest a specific diagnosis. Awareness of the specific time of occurrence, intensity of clinical symptoms, preferred localization, and extent of accompanying extraintestinal findings help to distinguish the different pathologic entities.

CT imaging of colitis

Computed tomography (CT) is widely used to assess patients with nonspecific abdominal pain or who are suspected of having colitis. The authors recommend multidetector CT with oral, rectal, and intravenous contrast material and thin sections, which can accurately demonstrate inflammatory changes in the colonic wall and help assess the extent of disease. In most cases, the final diagnosis of the type of colitis is based on clinical and laboratory data and colonoscopic and biopsy findings, but specific CT features help narrow the differential diagnosis. Ulcerative colitis is distinguished from granulomatous colitis (Crohn disease) in terms of location of involvement, extent and appearance of colonic wall thickening, and type of complications. Ulcerative colitis and Crohn disease (granulomatous colitis) are rarely associated with ascites, which is often seen in infectious, ischemic, and pseudomembranous colitis. Pseudomembranous colitis also demonstrates marked wall thickening and, occasionally, skip areas but is associated with broad-spectrum antibiotic treatment or chemotherapy. Neutropenic colitis is characterized by right-sided colonic and ileal involvement, whereas ischemic colitis is characterized by vascular distribution pattern and history. Diverticulitis is a focal asymmetric process with fascial thickening and inflamed diverticula. Dilatation of a thick-walled appendix with increased enhancement and adjacent stranding suggests appendicitis, but inflammatory changes may extend to the cecum and terminal ileum. Epiploic appendagitis is a focal rim-enhancing area next to the colon, usually without any substantial colonic wall thickening.

Colonic abnormalities on CT in adult hospitalized patients with Clostridium difficile colitis: prevalence and significance of findings

OBJECTIVE

The purpose of this study was to determine the prevalence of an abnormal colon on CT in adult inpatients with Clostridium difficile colitis, compare the clinical presentation of these patients, and determine whether CT findings predicted the need for surgical treatment.

MATERIALS AND METHODS

Over a 21-month period, 152 of 572 inpatients with C. difficile colitis were identified and had CT scans performed within 2 weeks of the diagnosis. These were independently and retrospectively reviewed by two reviewers. Those with colonic wall thickness greater than 4 mm were considered positive (CT-positive patients) and were further reviewed for specific findings in the colon. All 152 patients with CT scans were also retrospectively reviewed using the hospital information system for certain clinical parameters, admitting diagnoses, and reasons for scanning. The following were compared using several statistical tests: clinical parameters in CT-positive and CT-negative patients and surgical and nonsurgical groups to determine if positive scans or surgical treatment could be clinically predicted; specific CT findings in CT-positive patients to see if an association was found with clinical parameters or surgical treatment; and admitting diagnoses and reasons for scanning in scanned and unscanned populations to see which patients were more likely to undergo CT.

RESULTS

Seventy-six (50%) of 152 scanned hospitalized patients with C. difficile colitis were CT-positive. These patients most often had segmental involvement (50 [66%] of 76 patients), with the rectum (60 [82%] of 73 patients) and sigmoid colon (61 [82%] of 74 patients) most often affected. Positive scans were associated with increased WBC, abdominal pain, and diarrhea. Patients with signs and symptoms of infection or abdominal complaints were more likely to be scanned. No statistical correlation was found between specific CT findings and clinical parameters or clinical parameters and patients requiring surgery. There was no predictive value of specific CT findings for surgical treatment.

CONCLUSION

Half of the patients scanned had an abnormal CT, with segmental colonic disease more common than diffuse. Positive scans were more likely in patients with leukocytosis, abdominal pain, and fever. Specific CT findings did not correlate with clinical parameters and could not predict surgical treatment.

Pseudomembranous colitis revisited: spectrum of imaging findings

In recent years there has been a marked increase in the incidence of pseudomembranous colitis (PMC). PMC is more common in patients over 65 years of age and can cause significant morbidity. The purpose of this article is to review the imaging features of PMC on plain radiography, sonography, computed tomography (CT), scintigraphy and magnetic resonance imaging (MRI). It is important to recognize the imaging findings of PMC using different imaging methods and encourage urgent confirmation of the diagnosis serologically, as the differential includes other fulminant colitides for which colectomy may be the required. Awareness of the spectrum of imaging findings of PMC can help radiologists make the primary or incidental diagnosis of PMC.

The outcome of surgery in fulminant Clostridium difficile colitis

BACKGROUND

The clinical presentation of Clostridium difficile infection ranges from asymptomatic carriage, colitis with or without pseudomembranes, to fulminant colitis. Although not common, fulminant C. difficile colitis can result in bowel perforation and peritonitis with a high mortality rate. Colectomy is often indicated in these cases.

METHODS

We retrospectively analysed the outcome of 14 patients who underwent surgery for fulminant C. difficile colitis in the period 1996-2003 in our Unit.

RESULTS

The indications for surgery were systemic toxicity and peritonitis (n = 10), radiological and clinical evidence of progressive toxic colonic dilatation (n = 3) and progressive colonic dilatation with bowel perforation (n = 1). C. difficile infection as the cause of colitis was diagnosed pre-operatively in seven (50%) patients, six of whom underwent a total colectomy and one a right hemicolectomy. Overall mortality in our series was 35.7%. Total colectomy was associated with a lower mortality rate of 11.1% (1/9) when compared with left hemicolectomy was 100% (4/4) (P = 0.01). One patient who underwent a right hemicolectomy (on the basis of deceptively normal external appearance of the rest of the colon intra-operatively) survived after a prolonged hospital stay.

CONCLUSIONS

Early or pre-operative microbiological diagnosis of C. difficile infection can be difficult in patients with a fulminant presentation. Those patients with C. difficile colitis, who develop signs of toxicity, peritonitis or perforation, should undergo a total colectomy as the operation of choice.

Multi-detector computed tomography of acute abdomen

Acute abdominal pain is one of the most common causes for referrals to the emergency department. The sudden onset of severe abdominal pain characterising the "acute abdomen" requires rapid and accurate identification of a potentially life-threatening abdominal pathology to provide a timely referral to the appropriate physician. While the physical examination and laboratory investigations are often non-specific, computed tomography (CT) has evolved as the first-line imaging modality in patients with an acute abdomen. Because the new multi-detector CT (MDCT) scanner generations provide increased speed, greater volume coverage and thinner slices, the acceptance of CT for abdominal imaging has increased rapidly. The goal of this article is to discuss the role of MDCT in the diagnostic work-up of acute abdominal pain.

Sonographic diagnosis of colitis in children

To assist the radiologist in differentiating the colitis in children, this review proposes a systematic US approach to the disease, presents the US aspect of the normal colon and describes three distinctive US patterns reflecting the intramural extension of the histopathological changes. Each pattern corresponds to one or several diseases producing alterations in the same layer(s). Stratified thickening suggests an inflammatory mucosal process resulting from infection (as in advanced appendicitis or in infectious colitis) or to inflammation (as in IBD). Nonstratified thickening with loss of the haustral folds reflects a marked submucosal infiltrate. Color Doppler is required to distinguish between an inflammatory disease (as advanced CD or neutropenic colitis) and an ischemic colitis (HUS in children). Nonstratified thickening with preservation of the length of the haustral folds is the sign of an intraluminal deposit due to PMC. Correlating the sonographic pattern and the anatomic distribution of the disease with the clinical and laboratory findings often permits to propose a specific diagnosis.

Evaluating the CT diagnosis of Clostridium difficile colitis: should CT guide therapy?

OBJECTIVE

The purpose of this study was to further characterize the CT findings of Clostridium difficile colitis and to provide for the first time a diagnostic sensitivity, specificity, positive predictive value, and negative predictive value to help clinicians decide whether antibiotic treatment is warranted on the basis of CT findings while awaiting stool test results (which may take as long as 48 hr).

MATERIALS AND METHODS

A retrospective review covering a 4-year period was performed of the charts and CT scans of 54 symptomatic patients with stool test results positive for C. difficile and of a control group of 56 patients with antibiotic-associated diarrhea with stool test results negative for C. difficile.

RESULTS

At our institution, C. difficile colitis was explicitly diagnosed at CT in these patients with a sensitivity of 52%, specificity of 93%, positive predictive value of 88%, and negative predictive value of 67%. The sensitivity can be raised to 70% with no change in specificity with more rigid adherence to diagnostic criteria of colon wall thickening of greater than 4 mm combined with any one or more findings of pericolonic stranding, colon wall nodularity, the "accordion" sign, or otherwise unexplained ascites.

CONCLUSION

Although routine CT screening of antibiotic-associated diarrhea is not advocated, the 88% positive predictive value of a diagnosis of C. difficile colitis in those who are scanned may merit consideration of treatment by clinicians on the basis of the CT results alone.

CT evaluation of the colon: inflammatory disease

Computed tomography (CT) is valuable for detection and characterization of many inflammatory conditions of the colon. At CT, a dilated, thickened appendix is suggestive of appendicitis. A 1-4-cm, oval, fatty pericolic lesion with surrounding mesenteric inflammation is diagnostic of epiploic appendagitis. The key to distinguishing diverticulitis from other inflammatory conditions of the colon is the presence of diverticula in the involved segment. In typhlitis, CT demonstrates cecal distention and circumferential thickening of the cecal wall, which may have low attenuation secondary to edema. In radiation colitis, the clinical history is the key to suggesting the diagnosis because the CT findings can be nonspecific. The location of the involved segment and the extent and appearance of wall thickening may help distinguish Crohn disease and ulcerative colitis. In ischemic colitis, CT typically demonstrates circumferential, symmetric wall thickening with fold enlargement. CT findings of graft-versus-host disease include small bowel and colonic wall thickening, which may result in luminal narrowing and separation of bowel loops. In infectious colitis, the site and thickness of colon affected may suggest a specific organism. The amount of wall thickening in pseudomembranous colitis is typically greater than in any other inflammatory disease of the colon except Crohn disease.

Pseudomembranous colitis: spectrum of imaging findings with clinical and pathologic correlation

Pseudomembranous colitis (PMC) is a potentially life-threatening acute infectious colitis caused by one or more toxins produced by an unopposed proliferation of Clostridium difficile bacteria. PMC is characterized by the presence of elevated, yellow-white plaques forming pseudomembranes on the colonic mucosa. These plaques can be visualized at both pathologic analysis and endoscopy. Plain radiography, contrast enema studies, and computed tomography (CT) are useful in the evaluation of PMC. Plain radiography of the abdomen can demonstrate polypoid mucosal thickening, "thumbprinting" (wide transverse bands associated with haustral fold thickening), or gaseous distention of the colon. A toxic megacolon with distention and occasionally pneumoperitoneum may be seen in the most severe cases of PMC involving perforation. At contrast enema studies, the primary finding in mild cases of PMC is small nodular filling defects representing the mucosal plaques. With more extensive colonic involvement, the plaques are larger and coalesce to form an irregular bowel wall margin. Mural thickening and wide haustral folds caused by intramural edema may also be seen. A contrast enema study is contraindicated in patients with severe PMC due to the danger of perforation. Common CT findings include wall thickening, low-attenuation mural thickening corresponding to mucosal and submucosal edema, the "accordion sign," the "target sign" ("double halo sign"), pericolonic stranding, and ascites. Familiarity with these imaging characteristics may allow early diagnosis and treatment and prevent progression to more serious pathologic conditions.

The accordion sign at CT: a nonspecific finding in patients with colonic edema

PURPOSE

To determine whether the "accordion sign" is a specific computed tomographic (CT) sign of Clostridium difficile colitis.

MATERIALS AND METHODS

Fifty-seven patients with CT evidence of severe colitis, as judged by colonic wall thickening, an abnormal haustral pattern, the target sign, and stranding of the pericolic fat, were identified from a computerized CT database for 25 months. CT images were retrospectively evaluated for the presence of oral contrast material in the colon and for the accordion sign. The medical and laboratory records of all patients were reviewed and correlated with CT findings to establish the cause of colitis.

RESULTS

Oral contrast material had reached the colon in 35 of 57 patients at the time of the CT examination. The images in 15 of these patients demonstrated the accordion sign, and those in 20 patients did not. C difficile colitis was documented in four of the 15 cases displaying the accordion sign. In the remaining 11 patients, a different cause was documented. Oral contrast material had not reached the colon in the remaining 22 patients. Within this group with findings similar to the accordion sign, five patients had documented C difficile colitis, and four had colitis from other causes.

CONCLUSION

The accordion sign is indicative of severe colonic edema or inflammation, but it is not specific for C difficile colitis.

Pseudomembranous colitis: can CT predict which patients will need surgical intervention?

PURPOSE

Our purpose was to determine if patients with pseudomembranous colitis (PMC) requiring surgical intervention demonstrate radiographic features distinct from those of patients treated successfully with standard medical therapy.

METHOD

The indications for a CT study and the imaging findings from 17 patients who required laparotomy with colon resection for PMC were retrospectively reviewed. The CT findings were compared with the findings from 17 control patients (matched by clinical presentation) with PMC who were treated medically and did not require surgical intervention.

RESULTS

None of the CT findings evaluated in this study were significantly different between the surgical and nonsurgical groups. The CT findings evaluated for the surgical and nonsurgical groups, respectively, were as follows: wall thickness of the colon: 17.8+/-6.6 and 16.9+/-3.9 mm; largest caliber of the colon: 6.8+/-1.6 and 6.1+/-1.2 cm; presence of the accordion sign: 52.9 and 70.6%; heterogeneous contrast enhancement pattern (target sign): 57.1 and 57.1%; pericolonic stranding: 82.4 and 88.2%; ascites: 70.6 and 58.8%; pleural effusion(s): 64.7 and 64.7%; and subcutaneous edema: 64.7 and 64.7%.

CONCLUSION

Although none of the CT findings evaluated in this study was significantly different between the surgical and nonsurgical groups, CT was often the initial diagnostic modality in both groups. It is important for radiologists to recognize the CT appearance of PMC and suggest the diagnosis. However, patient triage may not be based solely on the CT findings.

Clostridium difficile-associated diarrhea and colitis: clinical manifestations, diagnosis, and treatment

PURPOSE

This review examines the pathogenesis, clinical manifestations, diagnosis, and current medical and operative strategies in the treatment of Clostridium difficile diarrhea and colitis. Prevention and future avenues of research are also investigated.

METHODS

A review of the literature was conducted with the use of MEDLINE.

RESULTS

C. difficile is a gram-positive, spore-forming bacterium capable of causing toxigenic colitis in susceptible patients, usually those receiving antibiotics. Overgrowth of toxigenic strains may result in a spectrum of disease, including becoming an asymptomatic carrier, diarrhea, self-limited colitis, fulminant colitis, and toxic megacolon. Diagnosis requires a high index of suspicion and depends on clinical data, laboratory stool studies (enzyme-linked immunoabsorbent assay and cytotoxin test), and endoscopy in selected cases. Protocols for treatment of primary and relapsing infections are provided in algorithm format. Discontinuation of antibiotics may be enough to resolve symptoms. Medical management with oral metronidazole or vancomycin is the first-line therapy for those with symptomatic colitis. Teicoplanin, Saccharomyces spp. and Lactobacillus spp., and intravenous IgG antitoxin are reserved for more recalcitrant cases. Refractory or relapsing infections may require vancomycin given orally or other newer modalities. Fulminant colitis and toxic megacolon warrant subtotal colectomy. Cost, in terms of extended hospital stay, medical and surgical management, and, in some cases, ward closure, is thought to be formidable. Review of perioperative antibiotic policies and analysis of hospital formularies may contribute to prevention and decreased costs.

CONCLUSION

C. difficile diarrhea and colitis is a nosocomial infection that may result in significant morbidity, mortality, and medical costs. Standard laboratory studies and endoscopic evaluation assist in the diagnosis of clinically suspicious cases. Appropriate perioperative antibiotic dosing, narrowing the antibiotic spectrum when treating infections, and discontinuing antibiotics at appropriate intervals prevent toxic sequelae.