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PubMed1994

Colonic findings in cirrhotics with portal hypertension. A prospective colonoscopic and histological study.

Total colonoscopy was performed in 38 consecutive cirrhotics (15 alcoholic, 19 postviral, four unknown) with portal hypertension, 32 of whom were enrolled in a program of esophageal sclerotherapy because of variceal bleeding (Child's grading: A, 13; B, 21; C, 4 patients). In 34 of them, multiple biopsies from the colonic mucosa were taken. Fifty non-cirrhotics (roughly matched for age and sex with the patients) who were colonoscoped because of atypical abdominal complaints, served as controls for rectal varices, polyps, and hemorrhoids. Rectal varices occurred in 3 of 38 (7.9%) of cirrhotics with portal hypertension; they were found only in those who had undergone esophageal sclerotherapy, but no association with the number of sclerotherapies was documented; severity and etiology of cirrhosis did not seem to influence their presence. Hemorrhoids and polyps did not seem to occur more frequently in cirrhotics than in controls. Nonspecific inflammatory changes were observed macroscopically in 57.9% of the patients; these were significantly more common in postviral cirrhosis in comparison with alcoholic cirrhosis (p = 0.01967; 95% CI, 0.757-0.155) and, in particular, in the Child's B postviral cirrhosis as compared with the Child's B alcoholic cirrhosis (p = 0.01915; 90% CI, 0.942-0.320). In 15 patients, there was histological evidence of chronic or acute nonspecific inflammation; no associations with the severity or the etiology of the cirrhosis were found. No vascular ectasias or ectasia-like lesions were found.

Adult↗
PubMed2001

Colonoscopic hydrostatic balloon dilatation of Crohn's strictures.

Recurrent strictures cause considerable morbidity among many patients with Crohn's disease. We present a retrospective review of the outcome of patients who underwent endoscopic hydrostatic balloon dilatation of Crohn's strictures in our hospital over the past 7 years. All patients were under observation at Addenbrooke's Hospital, Cambridge. An initial assessment of all strictures was made radiologically, and any patient with active disease was treated before consideration of endoscopic dilatation. Dilatation was carried out with Microvasive Rigiflex balloons. Outcome after dilatation was assessed by review at subsequent clinic visits. Sixteen of 22 patients had resolution of their obstructive symptoms after dilatation, although one third of patients required more than two dilatations over the follow-up period. Six of 22 patients had persisting symptoms after endoscopic treatment, requiring surgery. There were no complications noted after any of the 71 dilatations that were performed. We conclude that hydrostatic balloon dilatation is a safe and effective alternative to surgery in the management of Crohn's strictures within the reach of the colonoscope.

Adult↗
PubMed2003

Colonoscopic balloon dilation of Crohn's strictures: a review of long-term outcomes.

OBJECTIVE: To study the long-term outcomes of patients who have had endoscopic balloon dilation of Crohn's strictures. DESIGN: Retrospective case-note review over a 16-year period. PATIENTS: Patients with a Crohn's stricture causing obstructive symptoms and who had at least 6 months' follow-up data or a surgical outcome following dilation were sought; 59 patients (124 dilations) were identified. INTERVENTION: Patients all underwent endoscopic balloon dilation. RESULTS: Strictures were anastomotic in 53 patients (111 dilations) and de novo in six patients (13 dilations). The median stricture length was 3.0 cm. Median follow-up time was 29.4 months. Out of the total group, 41% of patients achieved long-term clinical benefit following dilation and in 17% after only a single dilation. The median number of dilations per patient was one. A total of 35 (59%) patients required surgery for their stricture during follow-up. There were two (1.6%) perforations as a result of dilation, one in an anastomotic stricture (managed conservatively) and one in a de-novo stricture (requiring surgery). There were no deaths. CONCLUSIONS: Colonoscopic balloon dilation of Crohn's strictures can achieve long-term clinical benefit in many patients. Repeat dilations are justified in initial non-responders. In this series, the procedure appears safe with low morbidity.

Adult↗
PubMed2005

Colonoscopic surveillance in inflammatory bowel disease.

PURPOSE OF REVIEW: To describe recent findings in the literature aimed at decreasing systematic error in dysplasia surveillance in inflammatory bowel disease. RECENT FINDINGS: Despite great promise, colonoscopic surveillance in inflammatory bowel disease has yet to be demonstrated to reduce colorectal cancer mortality. In part, this stems from a number of inherent systematic troubles, including low rates of observer agreement among pathologists; lack of consensus on the natural history of dysplasia, particularly low-grade dysplasia; the patchy nature of dysplasia, which leads to sampling error caused by insufficient biopsy by endoscopists; and incomplete patient follow-up. Recent publications that have focused on defining better the natural history of different levels of dysplasia and improving dysplasia identification at the time of colonoscopy may aid in overcoming the flaws of surveillance. The key recent findings include conflicting evidence on the relative danger of flat low-grade dysplasia, the safety of treating polypoid low-grade dysplasia as a benign adenoma in the absence of flat dysplasia in the rest of the colon or the surrounding mucosa, and preliminary support of chromoendoscopy to target dysplasia better during colonoscopy and to limit unnecessary nontargeted biopsies. SUMMARY: These and other advances stand a reasonable chance of making surveillance a more accurate tool to discriminate between patients with chronic colitis likely to progress to advanced pathology and those less likely to do so. Such advances may result in effective surveillance in which both colorectal cancer mortality and unnecessary colectomy may be limited.

Colonoscopy↗
PubMed1996

Mental retardation and colorectal disease: colonoscopic mass screening to determine whether the risk of adenomatous polyposis syndrome is increased in the mentally retarded.

Adenomatous polyposis syndrome (APS) is often associated with mental retardation, but whether there is a causal relationship between the two is unknown. This study was initiated to determine colorectal disease rates among mentally retarded subjects and whether they are at risk of developing colorectal cancer. Colonoscopic mass screenings were conducted to detect the presence of colonic neoplasms in 134 patients housed at an institution for the mentally retarded. The ages of these subjects ranged from 32 to 69 years (mean: 44 years) and their IQ scores ranged from 35 to 63. Screening presented no difficulties and the colonic regions up to the caecum were inspected in all patients. Polyps were found in 24 patients (17.9%), an abnormal fixation in two (1.5%), melanosis coli in two (1.5%) and haemorrhoids in two (1.5%). Thirteen subjects had a single polyp (54%), five had two polyps (21%), three had three polyps (12.5%) and three had four polyps (12.5%). Twenty one polyps were less than 5 mm in diameter, 14 were 5-9 mm and nine were 10 mm or larger. No cases of APS were detected during this mass screening programme. The mentally retarded patients in this study were not found to be at a high risk of developing either APS or colon cancer.

Adenomatous Polyposis Coli↗
PubMed2005

Segmental colonoscopic biopsies in the differentiation of ileocolic tuberculosis from Crohn's disease.

BACKGROUND AND AIM: The differentiation between Crohn's disease (CD) and tuberculosis (TB) of the intestine can be difficult in areas where both diseases occur. The present study examined histological criteria that would enable the diagnosis in mucosal biopsies. METHODS: Colonoscopic biopsies from 33 patients with TB and 31 patients with CD were examined for several specific histological features and their distribution. RESULTS: The salient distinguishing features of TB were granulomas larger than 400 microm in maximum dimension, more than four sites of granulomatous inflammation per site, cessation, a band of epithelioid histiocytes in ulcer bases and location of granulomas in the caecum. The salient features of CD were granulomas not showing any of the above features, focally enhanced colitis, pericryptal granulomatous inflammation, and the presence of architectural alteration/activity/chronic inflammation/deep ulceration at sites that did not show granulomatous response in the same or adjacent segments. Although granulomas in CD were distributed throughout the colon, they were more frequent in the rectosigmoid than in TB. All biopsies from endoscopically abnormal sites did not show distinguishing features of TB or CD, emphasizing the need for multiple biopsies. There was an accrual in the number of diagnoses made with increasing numbers of biopsies from rectum to ileum. CONCLUSIONS: Histology of mucosal biopsies can aid in the differentiation of TB from CD, but multiple biopsies from different colonic segments are important for complete evaluation.

Adult↗
PubMed1975

Large-bowel polypectomy via the colonoscope: experience with 80 polyps.

The experience of two colonoscopy units in managing 88 patients referred with 114 suspected colonic polyps are presented. Almost a quarter of the suspected polyps were artefacts, while some actual polyps were not visualized at the initial colonoscopy. All but 10 of the confirmed polyps were successfully snared. Morbidity was low. Five of the polyps were malignant. The technical aspect of snaring and of setting up colonoscopy units are discussed. It is considered that colonoscopic polypectomy is the optimum management of colonic polyps.

Adult↗
PubMed1993

Patient characteristics and pathology in colorectal adenomas removed by colonoscopic polypectomy.

Between September 1981 and August 1987 420 patients with 565 adenomas underwent colonoscopic polypectomy to produce a 'clean colon'. Data from these patients were analysed to identify associations between patient characteristics (age and sex), polyp characteristics (site, size, shape, multiplicity and villous content) and the degree of dysplasia in the index adenoma. In univariate analysis, severe dysplasia in the index adenoma was significantly but weakly associated with size (> or = 10 mm), peduncular shape and villous architecture. Logistic regression confirmed an independent effect only from villous architecture. These findings suggest that it is unlikely that strong predictors of a patient developing a metachronous adenoma or colorectal cancer can be identified on the basis of an index adenoma found at initial colonoscopy. These patients will continue to be followed to investigate this question.

Adenomatous Polyps↗
PubMed2002

Natural history of colorectal nonpolypoid adenomas: a prospective colonoscopic study and relation with cell kinetics and K-ras mutations.

OBJECTIVE: Serial colonoscopic observations were prospectively conducted to elucidate the natural history of nonpolypoid tumors. Furthermore, to clarify whether cell kinetic status affects the tumor development, proliferative indices, apoptotic indices, and K-ras codon 12 point mutations on biopsy specimens were investigated. METHODS: Seventy-five colorectal tumors, 13 polypoid and 62 nonpolypoid type (56 flat elevated and six depressed type) were studied. Proliferating and apoptotic cells were detected with anti-Ki-67 antibody and the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling method, respectively. Point mutations at K-ras codon 12 were examined by enriched polymerase chain reaction-based restriction fragment length polymorphism assay. RESULTS: The average follow-up period was 22 months (range 1-50). The lesions of subsequent exophytic growth, unchanged shape, depressed growth, and disappearance were observed in 0%, 92%, 0%, and 8% of polypoid type, in 39%, 39%, 13%, and 9% of flat elevated type, and in 33%, 67%, 0%, and 0% of depressed type, respectively. There was no significant difference in tumor size between initial and follow-up colonoscopy. Nonpolypoid tumors apparently changed to the exophytic growth during 2 yr or more. The tumors with exophytic growth had significantly higher proliferative indices/apoptotic indices ratios than those with unchanged morphology and disappearance/depressed growth (p < 0.05, respectively). K-ras codon 12 point mutations did not correlate with tumor development. CONCLUSIONS: Cell kinetic status plays an important role in determining minute colorectal tumor development, but not K-ras codon 12 mutations. Minute nonpolypoid adenomas frequently tend to grow slowly, and nearly 40% of those become the exophytic growth with time. Most of minute nonpolypoid tumors seem to follow the adenoma-carcinoma sequence.

Adenoma↗
PubMed2002

Colonoscopic miss rates determined by direct comparison of colonoscopy with colon resection specimens.

OBJECTIVES: Colonoscopy is an effective method for discovery of adenomas and for colon cancer screening and prevention. Studies evaluating back-to-back colonoscopies have estimated significant miss rates but are limited by the lack of a definitive gold standard. Our study evaluated the sensitivity of colonoscopy compared with examination of surgically resected colon as a gold standard. METHODS: This was a retrospective analysis of patients who had a portion of colon surgically removed and had lower endoscopy within 5 months. The focus of the review was not for the particular lesion for which the surgery was indicated but, rather, for the synchronous lesions in the portions of bowel that were removed. Sensitivity was determined by counting the number of lesions detected at colonoscopy compared with those found in the surgically resected segment. RESULTS: A total of 73 synchronous lesions were present in the resected segments of 156 patients. Colonoscopy detected 56 of 73 the lesions (sensitivity 76.7%: 95% CI = 67-86). Of the 17 missed lesions, 14 of 17 (82%, 95% CI = 64-100) were < 1-cm polyps. Endoscopy overlooked one 1-cm adenoma in the ascending colon. Two cancers were missed, both in the same patient in whom endoscopy detected a sigmoid cancer but missed synchronous lesions in the cecal and ascending colon. CONCLUSIONS: Colonoscopy is an effective method of finding cancers and polyps, but it is associated with significant miss rates for polyps <1 cm. The entire bowel should be carefully evaluated to exclude synchronous tumors in patients with known colorectal cancer. Further improvement of colonoscopic techniques and technologies is warranted.

Adult↗
PubMed2006

Evaluation of colonoscopic allergen provocation as a diagnostic tool in dogs with proven food hypersensitivity reactions.

OBJECTIVE: To evaluate the colonoscopic allergen provocation (COLAP) test as a new tool for the diagnosis of IgE-mediated food allergy. METHODS: Oral food challenges as well as COLAP testing were performed in a colony of nine research dogs with proven immediate-type food allergic reactions. In addition, COLAP was performed in five healthy dogs. RESULTS: When compared with the oral challenge test, COLAP accurately determined 18 of 23 (73 per cent) positive oral challenge reactions (73 per cent) in dogs with food allergies and was negative in the healthy dogs. CLINICAL SIGNIFICANCE: The accuracy of this new test may be higher than that for gastric sensitivity testing. Therefore, COLAP holds promise as a new test to confirm the diagnosis of suspect IgE-mediated food allergy in dogs.

Allergens↗
PubMed1973

Removal of polyps with fibreoptic colonoscope: a new approach to colonic polypectomy.

By using a colonoscope diathermy snare a total of 75 polyps have been removed from sites throughout the colon in 43 patients. There was some haemorrhage in four cases but no other morbidity, and all patients were discharged home within 24 hours. The ease of this procedure suggests that it should replace colotomy and surgical polypectomy in the management of polyps inaccessible to the rigid sigmoidoscope.

Adenoma↗
PubMed1980

Colonoscopic polypectomy in children.

Five children presenting with chronic and intermittent rectal bleeding were diagnosed as having colorectal polyps by fibreoptic colonoscopy performed under sedation. Three of the children had had barium-enema films reported on as normal. Eight polyps were seen, of which six were proximal to the sigmoid colon. All were removed endoscopically (one by proctoscopy, one by snare-intussusception) without complication. Colonoscopic polypectomy is a safe and efficient procedure in children, and colonoscopy may be regarded as first-line management in those with rectal bleeding.

Adolescent↗
PubMed1971

Clinical evaluation of fibreoptic sigmoidoscopy employing the Olympus CF-SB colonoscope.

Fifty-one patients with large bowel disease were examined with the Olympus CF-SB fibreoptic colonoscope. With adequate bowel preparation and employing inhalational analgesia administered by a self-demand valve the whole sigmoid colon could be examined in the majority of patients within 30 minutes. In 23% of cases (12/51) the diagnosis was either made or confirmed by this procedure alone. Fibreoptic sigmoidoscopy is especially helpful in patients with either equivocal or failed barium enemas and is indicated in patients with unexplained rectal bleeding, extending the search for polyps and cancer, and studying patients with inflammatory bowel disease.About one quarter of biopsies taken from a flat mucosal surface with the Olympus flexible biopsy forceps may be insufficient for detailed histology due to their small size. For this reason multiple biopsies may be taken. Adequate biopsies were always obtained from projecting lesions and could be very accurately sited. Colour photography employing automatic exposure control is used to supplement the information obtained. It is concluded that fibreoptic sigmoidoscopy is a valuable additional investigation in selected patients with suspected disease of the large bowel and to date has been without complications.

Anesthesia, Inhalation↗
PubMed2006

Pit patterns in rectal mucosa assessed by magnifying colonoscope are predictive of relapse in patients with quiescent ulcerative colitis.

BACKGROUND: Relapse of ulcerative colitis is difficult to predict by routine colonoscopy. A high-resolution video-magnifying colonoscope with chromoscopy enables the observation of colorectal mucosal pit patterns. AIMS: To investigate the association of pit patterns as assessed by magnifying colonoscopy (MCS) with histological inflammation and mucosal chemokine activity in patients with quiescent ulcerative colitis, and to prospectively analyse the prognostic factors that may predict exacerbations. METHODS: MCS was performed in 113 patients with ulcerative colitis in remission. Pit patterns in the rectal mucosa were classified into four MCS grades on the basis of size, shape and arrangement. Mucosal interleukin (IL) 8 activity was measured in biopsy specimens of rectal mucosa and the specimens were assessed for histological disease activity. The patients were then followed until relapse or for a maximum of 12 months. Multivariate survival analysis was carried out to determine the independent predictors of clinical relapse. RESULTS: A positive correlation was identified between MCS grade, histological grade (p = 0.001) and mucosal IL8 activity (p<0.001). Multivariate proportional hazard model analysis showed that MCS grade was a significant predictor of relapse (relative risk 2.06, p = 0.001). Kaplan-Meier estimate of relapse during 12 months of follow-up was found to increase with increasing MCS grade, with values of 0% for grade 1, 21% for grade 2, 43% for grade 3 and 60% for grade 4. CONCLUSION: MCS grading is associated with the degree of histological inflammation and mucosal IL8 activity in patients with quiescent ulcerative colitis, and may predict the probability of subsequent disease relapse in patients with ulcerative colitis in remission.

Adolescent↗
PubMed1993

Failure of colonoscopic surveillance in ulcerative colitis.

A prospective surveillance programme for patients with longstanding (> = 8 years), extensive (> = splenic flexure) ulcerative colitis was undertaken between 1978 and 1990. It comprised annual colonoscopy with pancolonic biopsy. One hundred and sixty patients were entered into the programme and had 739 colonoscopies (4.6 colonoscopies per patient; 709 patient years follow up). Eight eight per cent of examinations reached the right colon. There was no procedure related death. One Dukes's A cancer was detected. Forty one patients (25%) defaulted. Of these 25 remain well; 13 are unaccounted for, and one died from colonic cancer. One patient had colectomy for medical reasons, and another died of carcinoma of the pancreas. Retrospectively an additional 16 eligible patients were identified who had not been recruited. Of these, 14 remain well, two are unaccounted for. None developed colonic cancer. Four patients refused colonoscopy. All remain well. Over the same period seven other cases of colonic cancer were found in association with ulcerative colitis, two in patients who had erroneously been diagnosed as having only proctitis and were therefore not entered into the programme, but were found at operation to have total colitis, one in a patient with colitis of seven years duration, and four patients who had previously attended the clinic but had been lost to follow up before 1978 and then had represented with new symptoms during the surveillance period. Thus, of the nine colitis related cancers diagnosed in this centre during the study period only one was detected by the surveillance programme. The results of this large study, a a review of published works, cast doubts on the effectiveness of colonoscopic surveillance programmes in detecting colorectal cancer in patients with ulcerative colitis.

Adult↗
PubMed1997

Colonoscopic allergen provocation (COLAP): a new diagnostic approach for gastrointestinal food allergy.

BACKGROUND: The clinical relevance of gastrointestinal food allergy in adults is largely unknown because the mechanisms are poorly understood and the diagnosis is difficult to confirm. AIMS: To improve the diagnostic means for confirming intestinal food allergy on an objective basis, a new colonoscopic allergen provocation (COLAP) test was developed. PATIENTS: The COLAP test was performed in 70 adult patients with abdominal symptoms suspected to be related to food allergy, and in five healthy volunteers. METHODS: During the COLAP test, the caecal mucosa was challenged endoscopically with three food antigen extracts, a buffer control, and a positive control (histamine). The mucosal weal and flare reaction was registered semiquantitatively 20 minutes after challenge, and tissue biopsy specimens were examined for mast cell and eosinophil activation. RESULTS: No severe systemic anaphylactic reactions were found in response to intestinal challenge. The COLAP test was positive to at least one food antigen in 54 of 70 patients (77%), whereas no reaction in response to antigen was found in healthy volunteers. Antigen induced weal and flare reactions were correlated with intestinal mast cell and eosinophil activation, as well as with patients' history of adverse reactions to food, but not with serum concentrations of total or specific IgE or skin test results. CONCLUSION: The COLAP test may be a useful diagnostic measure in patients with suspected intestinal food allergy and may provide a new tool for the study of underlying mechanisms.

Adolescent↗
PubMed2001

Efficacy in standard clinical practice of colonoscopic polypectomy in reducing colorectal cancer incidence.

BACKGROUND: Colorectal cancer is one of the leading causes of death from cancer in Western countries. Removal of adenomas is based on the assumption that it could lead to a reduction in the incidence of colorectal cancer, as demonstrated by the National Polyp Study in the USA. A critical issue is whether the benefit observed in clinical trials can also be observed in standard clinical practice. To address the issue, a multicentre Italian collaborative study was organised. METHODS: The study cohort comprised 1693 subjects of both sexes, aged 40-69 years, enrolled between 1980 and 1987 following a total colon examination (TCE) (that is, total colonoscopy or colonoscopy and double contrast barium enema), with removal of at least one adenoma larger than 5 mm in diameter. Exclusion criteria were genetic syndromes, previous adenomas or colorectal cancer, previous colonic resection, inflammatory bowel disease, or sessile adenomas more than 3 cm in diameter. Follow up ended in December 1996 by TCE or telephone interview, and review of the medical records, clinical files, or death certificates. Incidence ratios for colorectal cancer were compared with expected age and sex specific incidences in the Italian general population. RESULTS: Follow up data were obtained for 97.3% of cases for a total of 14 211 person/years. Mean follow up was 10.5 years. Six colorectal cancer cases (four in males, two in females) at various stages were ascertained (one at 29 months, two at five years, one at seven years, one at eight years, and one at 10 years from the index examination). The number of cancers expected in the reference population was 17.7 for an incidence ratio of 0.34 (confidence interval 0.23-0.63; p<0.01). CONCLUSIONS: Colonoscopic polypectomy substantially reduced the incidence of colorectal cancer in the cohort compared with that expected in the general population. These results are of particular relevance considering that those with adenomas are at increased risk of colorectal cancer and that this retrospective study was performed on data obtained in standard clinical practice. This observation strengthens the concept of effective population screening in view of the fact that adenomatous polyps are the most frequent neoplastic outcome of screening and their removal is associated with a decrease in the incidence of colorectal cancer.

Adenoma↗