Is colonoscopy indicated for small adenomas found by screening flexible sigmoidoscopy?

BACKGROUND: There is controversy over whether patients who have a small tubular adenoma on screening flexible sigmoidoscopy should undergo colonoscopic examination of the proximal colon. OBJECTIVE: To prospectively determine the prevalence of advanced polyps in the proximal colon among patients who have small adenomas on screening sigmoidoscopy. DESIGN: Prospective cohort study. SETTING: A health maintenance organization and a Veterans Affairs medical center. PATIENTS: Asymptomatic patients older than 50 years of age who had no risk factors for colon cancer and underwent sigmoidoscopy. INTERVENTION: At the time of sigmoidoscopy, all polyps were biopsied and characterized. All patients with distal adenomas were offered colonoscopy. MEASUREMENTS: The size and histology of polyps identified by sigmoidoscopy and colonoscopy were noted. Polyps were considered advanced if they were larger than 10 mm or were tubulovillous, villous, or malignant. The prevalence of advanced proximal polyps was determined, and patients were stratified by the size and number of distal polyps found by sigmoidoscopy. RESULTS: Among 4490 patients who underwent sigmoidoscopy, a neoplastic lesion was detected in 401 (8.9%) and colonoscopy was done in 301 (75%). Of 90 patients with a single tubular adenoma 1 to 5 mm in diameter in the distal colon, 0% (95% CI, 0.0% to 4.0%) had an advanced proximal polyp compared with 5.4% (CI, 2.4% to 10.4%) of those who had multiple distal polyps 1 to 5 mm or 6 to 10 mm in diameter and 7.9% (CI, 2.6% to 17.6%) of those who had advanced distal polyps (P = 0.013 for trend). The low-risk group with a single tubular adenoma 1 to 5 mm in diameter represented 44% of all patients with distal adenomas or cancers found at flexible sigmoidoscopy. CONCLUSIONS: Among patients undergoing screening sigmoidoscopy, those with single tubular adenomas of 5 mm or less had a low prevalence of advanced proximal polyps. These patients may not benefit from colonoscopy.

Flexible sigmoidoscopy screening: patient acceptance.

Although compelling evidence is available that screening can reduce the risk of death from colon cancer, patient compliance with screening in the United States is poor. The objective of this study is to describe a program that uses patient education to improve patient acceptance of flexible sigmoidoscopy screening. Our program provides multiple opportunities for patients to ask questions and to receive information. Preliminary data show that this approach has resulted in a procedure acceptance rate of 81% of those referred in the first year of the program. Future research needs to focus on evaluating factors associated with noncompliance in colorectal cancer screening programs.

Clostridium difficile colitis.

Clostridium difficile has become one of the commonest pathogens of the lower intestinal tract. This organism appears unique in that infection almost always occurs during or after antibiotic therapy, suggesting that some component of the normal microflora prevents colonization by C. difficile. Once it has overgrown in the colon, C. difficile releases several toxins which cause tissue damage and diarrhea. Infection can range from a simple self-limited diarrheal illness to fulminant colitis with perforation and megacolon. Assay of stool filtrates reveals the presence of cytotoxin in nearly all patients with antibiotic-associated pseudomembranous colitis, and in approximately one third to one half of those with less severe infections. Effective therapy is available in the form of oral vancomycin, although the expense of this antibiotic has led to the use of oral metronidazole or bacitracin, which appear to be equally efficacious and considerably cheaper. Although we have learned a great deal about C. difficile in the past decade, a number of fascinating puzzles remain. We know very little about the immune response to this organism or its toxin, or whether a vaccine might someday be feasible. Similarly, we have very little insight into what effects antibodies exert on the normal colonic flora and how these effects allow C. difficile infection in a small percentage of patients. Studies of this pathogen will undoubtedly lead to a fuller understanding of the enormously complex and still mysterious microbial ferment which lives within our gastrointestinal tract.

The long-term outcome of restorative operation in Crohn's disease: influence of location, prognostic factors and surgical guidelines.

The course of all 113 patients with Crohn's disease whose initial procedure involved an anastomosis operated upon from 1942 to 1972 was followed through 1980. The calculated cumulative 30-year total mortality was 23.4%, 16.7% disease-related. The cumulative recurrence rate was 29% at five years, 52% at ten years, 64% at 15 years and 84% at 25 years, with no important differences between disease locations and types of operation. Sex, age, duration, granulomas, enteral or perirectal fistulas and length of the resection, the disease, and the proximal resection margin had no significant influence on the rates of development of recurrent disease or on functional outcome. By far the most common site of recurrence was the neo-terminal ileum, but in ileocolitis compared with ileitis, recurrence was 5.2 times more likely (p = 0.0001) to involve the adjacent or remote colon as well. Moreover, only 1/63 ileitis patients eventually required ileostomy, whereas 15/47 patients with ileocolitis or colitis ultimately required this procedure (p less than 0.001). The current status of the patients was excellent or good in 64% and unwell or dead related in 24%. Urolithiasis developed in 19%.

Therapeutic implications of Clostridium difficile toxin during relapse of chronic inflammatory bowel disease.

Clostridium difficile toxin was present in the stools of six patients with chronic inflammatory bowel disease during symptomatic relapse. Only two of these individuals had received antibiotics known to cause pseudomembranous colitis, and on proctoscopy none had pseudomembranes. In all patients disappearance of toxin, either with vancomycin therapy (five patients) or spontaneously (one patient), was associated with symptomatic improvement. Cl. difficile toxin may complicate chronic inflammatory bowel disease, and contribute to relapse in some patients.