Medline ® Abstracts for References 88-90
of 'Clostridium difficile infection in adults: Clinical manifestations and diagnosis'
Pseudomembranous colitis: spectrum of imaging findings with clinical and pathologic correlation.
Kawamoto S, Horton KM, Fishman EK
Radiographics. 1999 Jul-Aug;19(4):887-97.
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.
Department of Radiology, Saitama Medical School, Japan.
Prediction of complicated Clostridium difficile infection by pleural effusion and increased wall thickness on computed tomography.
Valiquette L, Pépin J, Do XV, Nault V, Beaulieu AA, Bédard J, Schmutz G
Clin Infect Dis. 2009;49(4):554.
BACKGROUND: Abdominal computed tomography (CT) is often used to evaluate complications in patients with Clostridium difficile infection (CDI), but no study has correlated CT findings with the risk of developing a complicated CDI. Furthermore, the value of CT has not been evaluated since the emergence of the BI/NAP1/027 hypervirulent strain of C. difficile. We sought to describe and correlate abdominal CT findings with complicated CDI and to compare them before and after the emergence of the epidemic strain.
METHODS: We conducted a retrospective cohort study of all hospitalized patients 18 years or older who, from 1 January 1998 through 31 December 2006, underwent abdominal CT within 72 h of their first positive stool sample.
RESULTS: Of 1189 patients with newly diagnosed CDI, 165 satisfied the inclusion criteria. Patients who underwent CT were younger, had higher peak white blood cell counts and serum creatinine levels, and were more likely to experience fever than those who did not undergo CT. No difference in CT findings was noted before and after the emergence of BI/NAP1/027 CDI. Pleural effusion (adjusted odds ratio [AOR], 2.6; 95% confidence interval [CI], 1.1-6.6), colonic wall thickness>15 mm (AOR, 6.0; 95% CI, 1.1-33.9), peak white blood cell count>or =30 x 10(9) cells/L (AOR, 4.8; 95% CI, 1.4-16.4), albumin level<20 g/L (AOR, 6.9; 95% CI, 2.4-20.1), and immunosuppression (AOR, 4.7; 95% CI, 1.5-15.3) were independently associated with complicated CDI.
CONCLUSIONS: In a selected sample of patients with CDI, CT provided prognostic information additional to what could be obtained from clinical and laboratory parameters. No change in CT characteristics was noted after the introduction of the BI/NAP1/027 strain in our center.
Department of Microbiology and Infectious Diseases, University of Sherbrooke, 3001, 12ème AveNord, Sherbrooke, Quebec J1H 5N4, Canada. Louis.Valiquette@USherbrooke.ca
An unexpected CT finding in a patient with abdominal pain.
Lim J, Phillips AW, Thomson WL
BMJ Case Rep. 2013;2013 Epub 2013 Jan 22.
A fit and well 16-year-old girl presented to the emergency department with signs and symptoms suggestive of appendicitis. A transabdominal ultrasound scan revealed a normal appendix but there was significant free fluid in the pelvis. Consequently, a CT scan of her abdomen was performed which showed mucosal oedema and inflammation involving virtually the entire length of her large bowel (the 'accordion sign'). Clostridium difficile colitis was thus suspected; however, the toxin was not detected in her stool. The patient was treated conservatively with intravenous fluids and antibiotics and had an uneventful recovery. She was subsequently discharged home 3 days later with a full recovery. In this case, the radiological appearance of the accordion sign which is traditionally known to be pathognomonic of pseudomembranous colitis, reveals that it may also be indicative of severe colonic luminal inflammation.
Department of General Surgery, Severn Deanery, Gloucester, UK.