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PubMed2002

The role of sigmoidoscopy and colonoscopy in the diagnosis and management of lower gastrointestinal disorders: endoscopic findings, therapy, and complications.

Flexible sigmoidoscopy and colonoscopy have revolutionized the clinical management of colonic diseases. Colonoscopy is a highly sensitive and specific test. Colonic diseases often produce characteristic colonoscopic findings, as well as characteristic histologic findings, as identified in colonoscopic biopsy or polypectomy specimens. Colonoscopy is relatively safe, with a low incidence of serious complications, such as colonic perforation, hemorrhage, cardiopulmonary arrest, or sepsis. Colonoscopy is becoming more important clinically because of more widespread use of screening colonoscopy for colon cancer, application of therapeutic colonoscopy, and exciting new technical improvements.

Angiodysplasia↗
PubMed1980

Endoscopic evaluation of inflammatory bowel disease.

The colonoscopic examination is not a routine procedure for patients with inflammatory bowel disease; colonoscopy does not supersede the double contrast barium x-ray examination as the diagnostic study of choice. The use of colonoscopy in patients with inflammatory bowel disease must be dictated by the particular clinical situation or nature of the problem and governed by the severity of colitis, the physical condition of the patient and the overall safety of the procedure in each instance. The judicious application of the colonoscopic examination in certain patients with inflammatory bowel disease yields important information concerning the nature, extent, and complications of the colonic inflammatory process, which heretofore has been unavailable for use in diagnosis and management of inflammatory bowel disease.

Colitis, Ulcerative↗
PubMed1978

Colitis, cancer, and colonoscopy.

Colonoscopy has added a new dimension to the diagnosis of colonic diseases. In the field of inflammatory bowel disease, colonscopy is indicated only when certain specific problems arise. Patients with acute colitis and those who are too sick to withstand cleansing enemas should not undergo colonoscopy. A major use of the colonoscope is in the detection of carcinoma in the colitic colon either in the form of colonic strictures or filling defects discovered by barium enema x-ray, or in the long-term surveillance of patients with universal ulcerative colitis. Criteria are listed to assist in the colonoscopic differential diagnosis between ulcerative and granulomatous colitis. By using different criteria than the radiographer, and with the help of biopsy specimens, a high degree of accuracy in proper diagnosis can be achieved.

Colitis↗
PubMed1998

Colorectal inflammation and increased cell proliferation associated with oral sodium phosphate bowel preparation solution.

Evidence is emerging that sodium phosphate (NaP), a commonly used oral cathartic agent, causes aphthoid ulcers or focal active colitis (FAC) in the colon and rectum. The aims of this study were (1) to assess the incidence of such ulcers diagnosed endoscopically ("aphthoid ulcers"), (2) to assess the incidence of histologically detected FAC and neutrophilic infiltration overlying lymphoid follicles ("aphthoid lesions"), and (3) to determine whether this effect of NaP is associated with epithelial cell proliferation. Aphthoid ulcers, unexplained by other diagnoses, were found in 18 of 687 consecutive patients (2.6%) who underwent colonoscopic examination after oral NaP preparation during a 12-month period; biopsy specimens showed FAC or aphthoid lesions. FAC was present in 11 of 316 patients (3.5%) who had biopsies but were endoscopically normal. Eight patients with aphthoid ulcers in the rectosigmoid showed no abnormalities when reexamined by flexible sigmoidoscopy after an interval as short as 7 days (range, 7 to 56 days). Mucosal biopsy specimens from these patients were assessed for apoptosis and epithelial proliferation by determining the MIB-1 labeling index (LI). The LI was increased by 136% after NaP preparation (55 +/- 6) compared with biopsy specimens obtained from the same patients during reexamination without NaP preparation (23 +/- 6, P = .01). This correlated with the number of apoptotic bodies per 10 colonic crypts (1.2 +/- 0.3 v 0.5 +/- 0.2, respectively). To determine whether these proliferative changes represent a response to mucosal ulceration, rectosigmoid biopsy specimens were compared in two additional patient groups: an NaP group in whom no gross lesions were evident and a no-NaP group who were not exposed to NaP. Although more modest, similar changes in the LI (42 +/- 4 and 30 +/- 3, respectively, P = .03) and in the occurrence of apoptotic bodies per 10 colonic crypts (1.3 +/- 0.4 and 0.4 +/- 0.1, respectively) were observed. We conclude that use of NaP is associated with increased colorectal crypt epithelial cell proliferation. This proliferative response to NaP exposure is evident in the absence of colonoscopically or other histologically recognizable abnormalities. In a proportion of patients, aphthoid ulcers, FAC, or aphthoid lesions serve as markers of mucosal damage by NaP.

Administration, Oral↗
PubMed1994

Are we telling patients the truth about surveillance colonoscopy in ulcerative colitis?

The recommended approach to the increased risk of colorectal carcinoma in ulcerative colitis has been colonoscopic surveillance rather than prophylactic colectomy. This strategy is based on the assumption that dysplastic lesions can be detected before invasive cancer has developed. We have analysed published reports on dysplasia surveillance to find out whether this assumption is valid. Ten prospective studies (1225 patients) satisfied our criteria. Of 40 patients with dysplasia-associated mass or lesion (DALM) detected, 17 (43%) already had cancer at immediate colectomy. The risks of cancer at immediate colectomy were 42% (10 of 24 patients) for high-grade and 19% (3 of 16) for low-grade dysplasia. Of 47 patients found to have high-grade dysplasia after the initial colonoscopy, 15 (32%) had cancer. 16-29% of patients with untreated low-grade dysplasia progressed to DALM, high-grade dysplasia, or cancer. Of patients with indefinite results, 28% progressed to high-grade dysplasia and 9% to cancer, so continued surveillance is essential. The risk of progression to dysplasia was only 2.4% for patients whose initial result was negative, so surveillance could perhaps be less frequent for these patients. Immediate colectomy is essential for all patients diagnosed with high-grade or low-grade dysplasia. A diagnosis of dysplasia does not preclude the presence of invasive cancer. We believe that patients should be informed about the limitations of colonoscopic surveillance so that they can take part rationally in decision-making about their management.

Colitis, Ulcerative↗
PubMed2003

Hereditary nonpolyposis colorectal cancer: preventive management.

Hereditary nonpolyposis colorectal cancer (HNPCC) is the most common form of hereditary colorectal cancer. Inherited mutations in the mismatch repair genes associated with this syndrome have an approximate 80% lifetime risk of colorectal cancer. Since there are no premonitory signs of susceptibility to HNPCC, family history is the initial method for identifying those at increased risk. At risk individuals should undergo genetic counseling and testing. Although an algorithmic indication for genetic testing in at risk HNPCC patients is yet to be determined, many advocate initial screening for microsatellite instability (MSI) of the cancer specimen in individuals suspected of carrying HNPCC mutations. Those who test positive for MSI can then undergo further testing for mutations in the associated germline mismatch repair genes. Techniques for detecting these mutations currently include in vitro synthesized-protein assay, single-strand conformational polymorphism, and DNA sequencing. Given the aggressive nature of HNPCC adenomas, individuals who test positive for HNPCC mutations are recommended to undergo yearly colonoscopic surveillance starting at the age of 25. A reasonable alternative to lifetime colonoscopic surveillance for the prevention of colorectal cancer in these individuals is prophylactic colectomy. The prevention of colorectal cancer through pharmacological means is under investigation as another option in the management of HNPCC patients. Specifically, chemoprevention trials are currently ongoing to evaluate the efficacy of COX-2 inhibitors in the prevention of colorectal cancer in HNPCC and familial adenomatous polyposis patients.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed2000

Management of gastrointestinal bleeding induced by gastrointestinal endoscopy.

Therapeutic gastrointestinal endoscopy has a much greater risk of inducing gastrointestinal hemorrhage than diagnostic endoscopy. For example, colonoscopic polypectomy has a risk of approximately 1.6% of inducing bleeding, compared with a risk of approximately 0.02% for diagnostic colonoscopy. Higher-risk procedures include colonoscopic polypectomy, endoscopic biliary sphincterotomy, endoscopic dilatation, endoscopic variceal therapy, percutaneous endoscopic gastrostomy, and endoscopic sharp foreign body retrieval. The risk of inducing hemorrhage is decreased by meticulous endoscopic technique. Hemorrhage from endoscopy may be immediate or delayed. Immediate hemorrhage should be immediately treated by endoscopic hemostatic therapy, including injection therapy, thermocoagulation, or electrocoagulation. Delayed hemorrhage generally requires repeat endoscopy for diagnosis and for therapy, using the same hemostatic techniques.

Endoscopy, Gastrointestinal↗
PubMed1990

Malignant lymphomatous polyposis: diagnosis and response to chemotherapy.

Malignant lymphomatous polyposis is a low-grade lymphoma with aggressive features. It may mimic polyposis coli on a barium enema and colonoscopic examination. An histological diagnosis may be made from a tissue biopsy taken via the colonoscope. We discuss the methods of diagnosis, the clinical behaviour and response to chemotherapy.

Aged↗
PubMedDate not supplied

Ogilvie's syndrome in the surgical patient: a new therapeutic modality.

Acute colonic pseudo-obstruction, Ogilvie's syndrome, most often appears as a complication of other clinical conditions. It is characterized by massive colonic dilation in the absence of a mechanical cause. Therapy for this condition has traditionally been colonoscopic decompression via a flexible colonoscope. We performed a retrospective study to assess the efficacy of Cystografin enema for colonic decompression in Ogilvie's syndrome. We present a series of 18 patients who developed Ogilvie's syndrome while hospitalized for trauma (n = 10), burn (n = 1), gastrointestinal surgery (n = 4), and hip replacement (n = 3). The mean pre-enema cecal size was 13 cm (range 10 to 15 cm). The mean postenema cecal size was 8.5 cm (range 6 to 15 cm). Fifteen of the 18 patients underwent Cystografin enema as the primary mode of decompression. Three had undergone prior colonoscopy, which had failed. One of the 18 patients required repeat enema for inadequate decompression after the first enema and one underwent colonoscopy for recurrence. Two patients underwent operative intervention after the enema. There were no complications related to the enema. In all patients we were able to rule out a mechanical cause of large bowel obstruction. We believe the safety, efficacy, and ease of this procedure make Cystografin enema optimal first-line treatment for acute colonic pseudo-obstruction.

Acute Disease↗
PubMed2004

Small early tubular adenomas and mixed colonic polyps found on screening flexible sigmoidoscopy do not predict proximal neoplasia in males.

BACKGROUND & AIMS: Distal colonic adenomas found on flexible sigmoidoscopy are associated with proximal neoplasias, thus requiring a complete colonoscopic examination, but data regarding the association of distal mixed polyps with proximal neoplasia are lacking. We conducted this study to elucidate the significance of distal mixed colonic polyps in predicting proximal neoplasia. METHODS: We retrospectively analyzed data from patients who underwent a flexible sigmoidoscopic examination for colorectal cancer screening and a follow-up colonoscopic examination because of distal colonic polyps. Distal index polyps were classified by a pathologist as early tubular adenoma (ETA), serrated, or true mixed categories. Index polyps also were immunostained with a monoclonal antibody, Adnab-9, a marker for the colorectal adenoma carcinoma sequence. RESULTS: In 636 patients with distal index polyps, 6% were malignant, 55% were adenomas, 13% were ETAs, 6% were serrated, 4% were true mixed, and 17% were hyperplastic. Compared with distal hyperplastic index polyps, distal malignant polyps (P = 0.0006) and adenomas (P = 0.001) were associated with a significantly increased number of synchronous proximal neoplasia, but the small distal mixed, serrated, or ETA did not predict the increased incidence of proximal neoplasia. Large distal polyps of each category were significantly associated with an increased number of synchronous proximal neoplasias. In support of these findings, immunostaining of distal polyps with Adnab-9 showed predictability for proximal neoplasia only in the adenoma category (P < 0.05). CONCLUSIONS: Small ETAs, serrated, or mixed polyps found on flexible sigmoidoscopic examination do not increase the probability of synchronous proximal neoplasia.

Adenomatous Polyps↗
PubMed2002

Cancer surveillance in ulcerative colitis: critical analysis of long-term prospective programme.

BACKGROUND: Patients with longstanding ulcerative colitis are at increased risk of colorectal cancer. In the literature, no agreement has yet been reached regarding prevention strategies. Our report sums up a prospective study started in 1980. METHODS: A total of 65 patients affected by ulcerative colitis for more than seven years were admitted to a regular colonoscopic and biopsy follow-up programme. RESULTS: Some 20 years after the beginning of the study, 23 (35.3%) patients have been operated upon, 2 patients have died but not from cancer 29 (44.66%) patients have abandoned the programme. Only 11 (16.9%) patients have remained under colonoscopic surveillance. CONCLUSION: These results cast some doubts on the significance of such a programme and on its long-term feasibility.

Aged↗
PubMed2003

An unusual endoscopic finding: Trichuris trichiura. Case report and review of the literature.

Detection of Trichuris trichiura during colonoscopic examination is an unusual finding, at least in developed countries. We report a case of a coincidental endoscopic diagnosis of whipworm infestation performed in a patient referred to our open-access endoscopy even before a faecal examination for ova and/or parasites had been performed. Review of literature on colonoscopic diagnosis of T. trichuria is provided.

Abdominal Pain↗
PubMed1999

Relationship of portal pressure and colorectal vasculopathy in patients with cirrhosis.

We studied the relationship between portal pressure and colorectal mucosal vascular lesions in cirrhotics and the effectiveness of drug therapy in treating these lesions. Colonoscopy and hepatic venous pressure gradient (HVPG) studies were performed in 21 cirrhotics. Oral spironolactone plus transdermal nitroglycerin were given to patients who had diffuse mucosal cherry-red spots and/or rectal varices. The colonoscopy and HVPG determinations were repeated after four weeks. Colonoscopic findings included vascular ectasias in 13 patients (62%), diffuse cherry-red spots in the rectum in five patients (24%), and rectal varices in eight patients (38%). Overall, colorectal mucosal vascular lesions were found in 16 cirrhotics (76%). These findings were not found in 21 age- and sex-matched noncirrhotic controls. Vascular ectasias appeared without relationship to the HVPG. Patients with diffuse cherry-red spots (N = 5, 22.4+/-3.4 mm Hg) had a significantly higher HVPG than those without (N = 16, 16.6+/-3.3 mm Hg, P < 0.01). However, no significant difference was found in HVPG between patients with rectal varices (N = 8, 19.4+/-4.6 mm Hg) and patients without rectal varices (N = 13, 17.2+/-3.8 mm Hg). After four weeks of drug therapy, diffuse cherry-red spots became less obvious when the HVPG decreased more than 20%. Rectal varices did not change their appearance with HVPG reduction. We found that colorectal vascular lesions are common in cirrhotics. Diffuse cherry-red spots are probably dependent on elevated portal pressure, but vascular ectasias and rectal varices are not related to the degree of portal pressure. Chronic drug therapy with reduction of portal pressure improves colonoscopic findings such as diffuse cherry-red spots.

Administration, Cutaneous↗
PubMed2003

Flat colonic adenomas in Malaysia: fact or fancy?

BACKGROUND: Some two-thirds of colorectal carcinomas arise from adenomatous polyps, and as such, screening by colonoscopy and polyp removal should significantly reduce colorectal cancer. This has not been the case, as evidenced by recent studies, which revealed that endoscopy failed to prevent up to 50% of all subsequent carcinomas. Flat or depressed adenomas, frequently reported from Japan but rarely elsewhere, might explain the 'missed carcinomas.' Detection of flat adenomas has not been previously reported from Malaysia. METHODS: In the present prospective study, 426 consecutive patients underwent colonoscopic examination between March 1997 and January 2000, for a variety of bowel symptoms. The examinations were performed by an experienced endoscopist using a standard colonoscope and methylene blue dye spraying technique. Macroscopically, flat adenomas were defined using the criteria proposed by Sawada. RESULTS: Twenty-nine adenomas were identified in 12 patients, of which 15 were polypoid and 14 were flat, with no depressed lesions. Eight polypoidal lesions and all the flat adenomas contained mild or moderate areas of epithelial dysplasia. Seven severely dysplastic polyps were identified. One Duke's A polypoidal cancer and two advanced carcinomas were also found. All the severely dysplastic lesions and Duke's A carcinomas were found in polyps greater than 10 mm in mean size. The flat adenomas were all less than 5 mm in size. CONCLUSIONS: A significant proportion of colonic adenomas in Malaysian patients appear as small flat lesions, which could easily be missed during endoscopy. Increased recognition and treatment of flat adenomas among colonoscopists is warranted.

Adenoma↗
PubMed2001

Screening of patients at high risk of colorectal cancer.

OBJECTIVE: To determine the present state of colonoscopic screening practice for patients at a high risk of developing colorectal cancer. METHODS: We assessed colonoscopic screening practice in nine colorectal surgery or gastroenterology units referring patients to the regional genetics centre in the North-west of England. The validity of the pedigree was confirmed by inspection of Hospital records, use of cancer registries and records of general practitioners across the United Kingdom. The screening activity at the participating centres was investigated by means of a questionnaire, site visit and study of case notes. RESULTS: One hundred and eight high risk families were identified. Outside the genetics unit, family history was not taken in a structured manner and family pedigree was not confirmed. In four units screening was offered directly by the consultant surgeon. Differing protocols for screening were in place in six units, but were frequently not adhered to. Colonoscopy completion rates were known in only four units (range 83-97%). Frequency of screening varied from 2 to 5 years. Recording of information was minimal outside the patients' records and there were no dedicated databases. Facilities for families to be screened together existed in three units and the psychological effect of screening was not determined outside the genetics centre. CONCLUSIONS: Screening practice should be standardized and specific criteria met before regular screening is initiated. A dedicated database should be established to record information from units screening patients at high risk of colorectal cancer.

Journal Article↗
PubMed2002

Leukocyte apheresis using a centrifugal cell separator in refractory ulcerative colitis: a multicenter open label trial.

Recently, successful results of ulcerative colitis (UC) treatments with leukocyte apheresis have been reported by several institutes. To certify the efficacy of leukocyte apheresis in refractory UC patients, a multicenter open label trial was conducted, and results were analyzed. Fifty patients diagnosed with active steroid-resistant UC were enrolled in this study from 14 medical centers. Using a centrifugal cell separator (Component Collection System, Haemonetics), leukocyte apheresis was performed once a week for 5 weeks. General conditions and abdominal symptoms were recorded daily, and laboratory tests were followed weekly. Changes of colonoscopic and histological manifestations of luminal activity through the study period were evaluated. At the end of the study period, stool frequency was decreased to less than 4 times a day in 68.4% (26 of 38) and serum C-reactive protein (CRP) concentration was normalized in 56.7% (17 of 30) of the patients. Colonoscopic remission was achieved in 57.7% (26 of 45), and histological improvement was noted in 54.1% (20 of 37) of the patients tested. Improved disease activity was demonstrated in 74% (37 of 50) of the patients by general assessment criteria. Analysis of the trial data confirmed the valid clinical efficacy of leukocyte apheresis by centrifugal cell separator in refractory UC patients.

Adult↗
PubMed1996

Risk and natural history of colonic neoplasia in patients with primary sclerosing cholangitis and ulcerative colitis.

BACKGROUND & AIMS: Primary sclerosing cholangitis (PSC) has been suggested as a risk factor for the development of colorectal cancer in ulcerative colitis (UC); however, previous studies of this association have been limited by small numbers of patients with PSC or have been performed retrospectively. This study prospectively evaluates the risk and natural history of colonic tumorigenesis in patients with PSC and UC and compares it with patients with UC without PSC. METHODS: Twenty patients with PSC and UC and 25 control patients with UC were followed prospectively by colonoscopic surveillance using extensive mucosal biopsy sampling. All control patients with UC had disease extending beyond the sigmoid colon of > or = 8 years' duration; patients with PSC and UC were studied regardless of disease duration. RESULTS: Forty-five percent (9 of 20) of the patients with PSC and UC had dysplasia compared with 16% (4 of 25) of the control patients with UC (P < or = 0.002). Prior liver transplantation did not affect the risk of colonic dysplasia. The time course for progression to dysplasia was similar between the patients with PSC and UC and the patients with UC; however, the patients with PSC and UC were five times more likely to develop dysplasia. CONCLUSIONS: Patients with PSC and UC represent a subset of patients with UC who are at markedly increased risk for colonic neoplasia and who need close colonoscopic surveillance with extensive biopsy sampling.

Adult↗
PubMed2002

Activation of the mucosal immune system in irritable bowel syndrome.

BACKGROUND & AIMS: A role for the mucosal immune system in the pathogenesis of irritable bowel syndrome is suggested by its association with intestinal infections. METHODS: To investigate this, we performed histologic and immunohistologic studies on colonoscopic biopsy specimens from 77 patients with symptoms satisfying the Rome criteria and 28 asymptomatic control patients. RESULTS: Histologic assessment of biopsy specimens from symptomatic patients indicated 3 different groups. The first (38 of 77) had normal conventional histology; however, immunohistology showed increased intraepithelial lymphocytes (median, 1.8-fold; range, 1.74-1.86), lamina propria CD3(+) cells (2-fold; range, 1.55-2.91), and CD25(+) cells (6.5-fold; range, 4.98-8.13) compared with asymptomatic controls. The second group (31 of 77) had nonspecific microscopic inflammation and on immunohistology showed similar increases in lymphocyte populations (not significant vs. the uninflamed group) as well as increased numbers of neutrophil leukocytes and mast cells (P < 0.0001 vs. controls and the uninflamed group). The third group (8 of 77) fulfilled histologic and immunohistologic criteria for classic lymphocytic colitis. CONCLUSIONS: Examination of colonoscopic biopsy specimens from patients meeting the Rome criteria for a clinical diagnosis of irritable bowel syndrome showed subgroups with normal and abnormal conventional histology. All groups showed increased numbers of activated immunocompetent cells in the intestinal mucosa on quantitative immunohistology, implicating the mucosal immune system in pathogenesis.

Adult↗