Backwash ileitis is strongly associated with colorectal carcinoma in ulcerative colitis

Colorectal cancer in patients with inflammatory bowel disease

Patients with inflammatory bowel disease (IBD) are subject to increased risks for the development of colorectal cancer (CRC), risks that are attributed to the duration and anatomic extent of disease in patients with ulcerative colitis and Crohn's disease. Although IBD contributes only 1%-2% to all cases of CRC, the mortality rate in patients with a diagnosis of CRC in the setting of IBD is higher than for those afflicted with sporadic cases of CRC. Given the length of time from IBD onset to the development of CRC, surveillance continues to be widely practiced. Although still under development, novel techniques for the earlier detection of dysplastic lesions have moved to the forefront in an attempt to optimize surveillance strategies and decrease the risk of CRC development.

Ileostomy adenocarcinomas in the setting of ulcerative colitis

Adenocarcinomas arising at ileostomy sites in patients after colon resection for various diseases, such as ulcerative colitis (UC), familial adenomatous polyposis coli, and Crohn's disease, are rare occurrences but have been reported increasingly in the last 20 years. We report a case of adenocarcinoma arising in an ileostomy site in an 85-year-old woman with longstanding UC. She had pancolitis and underwent total proctocolectomy. Thirty-nine years later, her ileostomy site developed a granulation tissue-type lesion, which on initial biopsy revealed cytologic atypia in the presence of marked inflammation. A subsequent biopsy revealed adenocarcinoma with signet-ring cells and abundant extracellular mucin. Resection of the ileostomy was undertaken and a new ileostomy was performed. The literature on adenocarcinoma arising in the 23 patients with ulcerative colitis who received a Brooke or Kock ileostomy and had no prior history of neoplasm is reviewed.

The histological diagnosis of dysplastic and neoplastic lesions in inflammatory bowel disease: a pathological perspective

Patients with inflammatory bowel disease (IBD), both ulcerative colitis (UC) and Crohn's disease (CD), are at an increased risk for developing colorectal carcinoma (CRC). The accurate diagnosis of dysplasia in biopsies taken during periodic surveillance of long-standing IBD patients is most important in prevention of UC and CD related cancer. Distinction of low from high grade IBD-related dysplasia and differential diagnosis between IBD-related dysplasia and dysplasia in sporadic adenoma as well as distinction from pseudodysplastic lesions in inflammatory pseudopolyps or reparative lesions is often very subtle and difficult and demands expertise of second experienced gastrointestinal pathologist. Although surveillance colonoscopy with multiple biopsies does not reduce the cancer mortality, it offers a reasonable chance of detecting precancer and performed prophylactic colectomy. Novel methods of detecting dysplasia are continuously being evaluated, including chromoscopy and molecular biology markers. In the future, one may expect, from these new markers to detect the dysplasia in IBD patients before development of histological evidence of neoplastic changes.

Diagnosis and management of dysplasia in patients with inflammatory bowel diseases

Patients with ulcerative colitis and Crohn's colitis face an increased lifetime risk of developing colorectal cancer. Factors associated with increased risk include long duration of colitis, extensive colonic involvement, primary sclerosing cholangitis, a family history of colorectal cancer, and, according to some studies, early disease onset and more severely active inflammation. Although prophylactic proctocolectomy can essentially eliminate the risk of cancer, most patients and their physicians opt instead for a lifelong program of surveillance. This entails regular medical follow-up, management with antiinflammatory and putative chemopreventive agents, and periodic colonoscopic examinations combined with extensive biopsy sampling throughout the colon. The main objective of regular colonoscopy is to detect neoplasia at a surgically curative and preferably preinvasive stage, i.e., dysplasia. An initial screening colonoscopy should be performed 7-8 years from disease onset or immediately in patients with primary sclerosing cholangitis. Surveillance should then continue annually or biennially so long as no dysplasia is found or suspected. Biopsy specimens are graded pathologically as negative, indefinite for dysplasia, low-grade dysplasia, high-grade dysplasia, or invasive cancer. The diagnosis and grading of dysplasia can be very challenging and should be confirmed by an expert pathologist whenever intervention or a change in management is contemplated. If 1 or more biopsy specimens are indefinite for dysplasia, colonoscopy intervals should be reduced. A patient with low- or high-grade dysplasia found in a discrete adenoma-like polyp, but nowhere else, can be safely managed with polypectomy and accelerated surveillance. However, dysplasia of any grade found in an endoscopically nonresectable polyp and high-grade dysplasia found in flat mucosa are both strong indications for proctocolectomy. Evidence further suggests that the same may be true even of low-grade dysplasia in flat mucosa. Chromoendoscopy holds promise for facilitating the endoscopic detection of neoplasia. The clinical application of newer molecular methods to detect neoplasia, particularly gene microarrays and stool DNA testing, also deserve further study.

Noninfectious liver disorders: assessment and diagnosis

Infectious hepatitis is often the initial suspect when abnormal serum liver function test results are discovered in primary care settings. However, noninfectious liver disorders may also present with altered liver function tests. Noninfectious liver disorders require careful assessment of patient history, physical findings, and serum laboratory tests to distinguish among entities that have varying clinical implications and treatments.

Gross versus microscopic pancolitis and the occurrence of neoplasia in ulcerative colitis

OBJECTIVE

The gross extent of ulcerative colitis (UC) is a recognized risk factor for the development of colitis-related dysplasia and colorectal cancer (CRC). The risk of neoplasia associated with the microscopic extent of colitis is unknown. The aim of this study was to describe the gross and microscopic extent of colitis in patients with UC-related dysplasia/CRC.

METHODS

All patients who underwent colectomy at our institution between 1992-2001 with colitis-related dysplasia/CRC were identified. Histological sections from each colectomy specimen were reviewed for the microscopic extent of colitis and the location of all lesions with dysplasia/CRC.

RESULTS

Thirty-six patients with colitis-related dysplasia/CRC were identified of whom 30 had slides available for review. Gross pancolitis was identified in 19 patients, though microscopic pancolitis was evident in all 30 patients. Among the 11 patients with only distal gross colitis, 4/15 neoplastic lesions were proximal to the area of gross involvement.

CONCLUSIONS

UC-related neoplasia can occur in areas of the colon not grossly involved with colitis, though it did not occur in any patients without microscopic pancolitis. To devise rational cancer surveillance guidelines, further studies are needed to determine the risk of colitis-related neoplasia in patients with microscopic pancolitis but limited gross disease.

Review article: colitis-associated cancer -- time for new strategies

Colorectal cancer (CRC) remains a feared and potentially life-threatening complication of both ulcerative colitis and Crohn's colitis. Currently, the main preventive strategy is a secondary one, i.e. surveillance colonoscopy usually after 8 years of disease duration, when the risk for neoplasia begins to increase. Despite its widespread acceptance, dysplasia and cancer surveillance is unproven in terms of reducing mortality or morbidity and there is a remarkable lack of uniformity in the manner in which it is practised. In this review article, the pitfalls of dysplasia surveillance are summarized and the need for novel chemopreventive and perhaps pharmabiotic approaches for prevention are highlighted.

Aminosalicylates and colorectal cancer in IBD: a not-so bitter pill to swallow

Inflammatory bowel disease (IBD) is associated with an increased risk of developing intestinal cancer at sites of chronic inflammation. Aminosalicylates, including both sulfasalazine and mesalamine, are the most commonly prescribed anti-inflammatory agents prescribed in IBD. On balance, the body of literature to date suggests that aminosalicylates confer some protection against the development of colonic neoplasia in patients with IBD and in a variety of models, including in the noninflamed gut. This latter observation implies that aminosalicylates may be of chemopreventive value in normal as well as IBD individuals. The current review examines and gives an overview of the evidence from a variety of sources, including epidemiological, in vivo and in vitro studies that have investigated the potential anticancer effects of aminosalicylates.

Inflammatory bowel disease and liver transplantation for primary sclerosing cholangitis

OBJECTIVES

To compare the outcome of liver transplantation in primary sclerosing cholangitis (PSC) patients with and without inflammatory bowel disease (IBD), and to analyse the influence of the transplantation on the course of IBD.

METHODS

Retrospective analysis of the data regarding PSC, IBD, and liver transplantation in all patients transplanted for PSC.

SETTING

Single university transplantation centre.

RESULTS

Thirty-one patients were transplanted for PSC, of whom 18 had IBD before liver transplantation. There were no differences in complication rate and outcome between patients with and patients without IBD. Before liver transplantation, the IBD course was active in three patients and quiescent in 14 patients (one patient was not evaluable). After liver transplantation, the course was active in five (one de-novo IBD) patients and quiescent in 13 patients. Exacerbations of IBD occurred in ten patients during treatment with steroids and a calcineurin blocker. Five patients with long-standing and extensive colitis developed colorectal neoplasia after liver transplantation (two colorectal cancer, two extensive dysplasia, one leiomyosarcoma).

CONCLUSIONS

Concomitant IBD had no detrimental influence on the outcome of liver transplantation in patients with PSC. The course of IBD was not altered after liver transplantation. Immunosuppression including steroids did not prevent exacerbations of IBD. The development of colorectal neoplasia is a serious threat to patients with IBD and PSC after liver transplantation.

Does monitoring prevent cancer in inflammatory bowel disease?

Surveillance colonoscopy for patients who have inflammatory bowel disease with colonic involvement has gained widespread acceptance. From an evidence-based perspective, however, the foundation for this practice remains weak. There are no randomized controlled trials, prospective cohort studies, or case-control studies that definitively prove a benefit for surveillance colonoscopy (i.e., reduction in colorectal cancer-related mortality). Nevertheless, circumstantial evidence indirectly suggests a benefit. This article reviews risk factors for colorectal cancer in inflammatory bowel disease and the evidence supporting the practice of colonoscopic surveillance. The benefits of frequent physician visits and compliance with medication regimens with regard to reduction in colorectal cancer risk are also reviewed.

Methylene blue-aided chromoendoscopy for the detection of intraepithelial neoplasia and colon cancer in ulcerative colitis

BACKGROUND & AIMS

Timely diagnosis of intraepithelial neoplasias (IN) and colitis-associated colon carcinomas (CRC) is crucially important for the treatment of ulcerative colitis (UC). We performed a randomized, controlled trial to test whether chromoendoscopy (CE) might facilitate early detection of IN and CRC in UC.

METHODS

A total of 263 patients with long-standing UC (>or=8 years) were screened for potential inclusion in the study, 165 of whom were randomized at a 1:1 ratio to undergo conventional colonoscopy or colonoscopy with CE using 0.1% methylene blue. Five mucosal biopsy specimens were taken every 10 cm between the rectum and cecum. Circumscript lesions in the colon were evaluated according to a modified pit pattern classification.

RESULTS

In the CE group, there was a significantly better correlation between the endoscopic assessment of degree (P = 0.0002) and extent (89% vs. 52%; P < 0.0001) of colonic inflammation and the histopathologic findings compared with the conventional colonoscopy group. More targeted biopsies were possible, and significantly more IN were detected in the CE group (32 vs. 10; P = 0.003). Using the modified pit pattern classification, both the sensitivity and specificity for differentiation between non-neoplastic and neoplastic lesions were 93%.

CONCLUSIONS

Based on our prospective randomized trial, CE permits more accurate diagnosis of the extent and severity of the inflammatory activity in UC compared with conventional colonoscopy. In addition, CE with methylene blue is a novel tool for the early detection of IN and CRC in patients with UC. These findings have important implications for medical and surgical interventions.

Diagnostic problems and advances in inflammatory bowel disease

This review summarizes current diagnostic problems and advances with regard to patterns of inflammation and dysplasia in ulcerative colitis and Crohn's disease. Ulcerative colitis and Crohn's disease have a variety of characteristic but non-specific pathologic features. In approximately 5% of inflammatory bowel disease cases, a definite diagnosis of ulcerative colitis or Crohn's disease cannot be established, in which case the term "indeterminate" colitis is used. Most cases of indeterminate colitis are related to fulminant colitis, a condition in which the classic features of ulcerative colitis or Crohn's disease may be obscured by severe ulceration with early superficial fissuring ulceration, transmural lymphoid aggregates, and relative rectal sparing. Approximately 20% of patients with indeterminate colitis develop severe pouch complications, which is intermediate in frequency between ulcerative colitis (8-10%) and Crohn's disease (30-40%). In order to establish a diagnosis of ulcerative colitis or Crohn's disease, it is important to evaluate pathologic material in conjunction with clinical, laboratory, radiologic, and endoscopic features and to recognize the variety of changes that may be seen in fulminant ulcerative colitis. There are a number of exceptions to the classic principles of inflammatory bowel disease pathology that may lead to diagnostic confusion. For instance, apparent skip lesions on biopsy analysis may occur in patients with ulcerative colitis in the following settings; long term oral or topical therapy, focal ascending colon, cecum and/or appendiceal involvement in patients with left sided ulcerative colitis, upper gastrointestinal involvement in patients with ulcerative colitis, and at initial presentation of ulcerative colitis in pediatric patients. In all of these circumstances, the finding of patchy disease and/or rectal sparing should not be misinterpreted as either evidence against a diagnosis of ulcerative colitis, or as representing skip areas characteristic of Crohn's disease. Patients with ulcerative colitis and Crohn's disease are at increased risk for the development of dysplasia and carcinoma. Recent studies suggest that given a similar duration and extent of disease, patients with Crohn's disease have a similar risk of dysplasia and cancer as patients with ulcerative colitis. Dysplasia in ulcerative colitis may be classified as flat or elevated (dysplasia associated lesion or mass [DALM]). Patients with flat high grade dysplasia are generally treated with colectomy. However, there is recent evidence to suggest that patients with flat low grade dysplasia, particularly if detected at the time of initial endoscopic exam, or if its multifocal or synchronous, should also be treated with colectomy. Elevated lesions in ulcerative colitis (DALM) are subdivided into "adenoma-like" and "non-adenoma-like" lesions based on their endoscopic appearance. Recent data suggests that adenoma-like lesions, regardless of the grade of dysplasia, or the location of the lesion (i.e., inside or outside areas of established colitis) may be treated adequately by polypectomy if there are no other areas of flat dysplasia in the patient. Although there are some histologic and molecular features that can help differentiate sporadic adenomas from adenoma-like polypoid dysplastic lesions related to ulcerative colitis, none of these adjunctive techniques can help distinguish these lesions definitively in any single patient. Patients with a non-adenoma-like DALM, (irregular, broad based, or strictured lesion) should be treated with colectomy because of the high probability of adenocarcinoma. The surveillance and treatment options for patients with flat and elevated dysplasia in ulcerative colitis are reviewed in detail.

Malignancies in inflammatory bowel disease: fact or fiction?

BACKGROUND

The association between ulcerative colitis (UC), Crohn disease (CD) and colorectal cancer (CRC) has been confirmed in several studies. The aim of this study was critical analysis of the relation between IBD and malignancy.

METHODS

Review of the literature.

RESULTS

In UC, the extent of the disease, its duration and start at a young age are risk factors for the development of CRC. Primary sclerosing cholangitis and colonic strictures are additional risk factors for development of CRC. The relation between azathioprine or 6-MP and the development of lymphomas is a subject of debate. The administration of anti-TNF-alpha has produced some concern about the development of lymphomas in CD. However, at present there is no evidence of lymphomas caused by anti-TNF-alpha in CD. On the contrary, some drugs seem to have a preventive effect on CRC development in UC. 5-aminosalicylic acid in particular and to a lesser extent sulphasalazine have prevented the development of CRC significantly in retrospective studies. In CD, there is no strong relationship between the disease and the development of CRC or other malignancies. Only the development of small-bowel carcinoma is reported with a much higher frequency.

CONCLUSIONS

There is a correlation with UC and the development of CRC. For CD, this correlation is less firmly established. There is a possible, but not proven, relation between AZA/6-MP use and the development of lymphoma in IBD. There is also a probable relationship between CD and the development of small-bowel carcinoma. In some retrospective studies, the use of 5-aminosalicylic or sulphasalazine has been shown to prevent the development of CRC in UC.

Screening for p53 and K-ras mutations in whole-gut lavage in chronic inflammatory bowel disease

OBJECTIVES

Molecular screening for frequently mutated genes may increase the likelihood of identifying cancer risk groups, such as patients with longstanding inflammatory bowel disease. This study investigated the prevalence and time course of p53 and K-ras mutations in colonic lavage fluid of patients with inflammatory bowel disease.

METHODS

Colonic lavage fluid from 190 patients with ulcerative colitis (73), Crohn's disease (58) or controls (49 non-tumour, 10 colorectal cancer) was studied by oligomer-specific hybridization for K-ras mutations and single-strand conformation polymorphism (SSCP) for p53 mutations. Follow-up investigations were carried out after 1-3 years.

RESULTS

Mutations were most frequent in carcinomas (5/10, 50%) and rare in non-tumour controls (1/49, 2.0%). They were found in Crohn's colitis in 15.4%, in extensive ulcerative colitis in 18.6%, in left-sided ulcerative colitis in 13.3%, and in distal ulcerative colitis in 6.7% (P > 0.05). There was a positive association with disease duration (> or =11 years, P < 0.05). Follow-up investigations detected the same mutation in four patients and revealed new mutations in three patients.

CONCLUSIONS

In our large series of patients with inflammatory bowel disease, K-ras and p53 mutations could be detected with reasonable frequency and confirmed at follow-up in at least some patients. Our data encourage the use of molecular screening for the detection of malignant precursor lesions in at-risk patients.

Cancer prevention in inflammatory bowel disease and the chemoprophylactic potential of 5-aminosalicylic acid

The risk of colorectal cancer is increased in ulcerative colitis and Crohn's colitis. Regular dysplasia surveillance colonoscopy in chronic colitis generally has been adopted as a strategy to prevent colorectal cancer or at least to diagnose it in an earlier stage. This has not been proven to reduce mortality, but it does provide the clinician and the patient with some confidence that they are participating in an active strategy to deal with the problem of colorectal cancer in chronic colitis. Disease extent and duration have long been held to be risk factors for colorectal cancer in chronic colitis, and recently some special risk groups have been identified which may require either more intensive surveillance or alternative approaches to cancer prevention. These include patients with primary sclerosing cholangitis, patients with first-degree relatives with sporadic colon cancer, and possibly, patients with backwash ileitis. There is an emerging interest in potential chemopreventative strategies in both sporadic and colitis-associated colorectal cancer. There also have been suggestive data that chronic maintenance 5-aminosalicylate use might reduce the risk of developing colorectal cancer. Recent data have suggested some potential preventative benefit of using ursodeoxycholic acid in patients with ulcerative colitis and primary sclerosing cholangitis. The scientific rationale for using these agents is sound but clinical data are lacking to fully support these approaches as chemoprevention in chronic colitis at present.

Colonic dysplasia and cancer in inflammatory bowel disease

Extracolonic malignancies are a relatively rare complication of inflammatory bowel disease. In contrast, colorectal cancer remains a major concern for patients with long-standing UC. The best available evidence suggests that patients with long-standing Crohn's colitis are at similar risk for colorectal cancer as those patients with long-standing UC. In patients with UC, the magnitude of this increased risk appears to be greater in patients with more extensive colonic involvement. It appears that the magnitude of this risk increases with increasing duration of disease, at least in UC. Whether this reflects the increased risk of cancer that occurs with the aging process or a separate phenomena distinct to UC is unclear. To date, the methods available to reduce the risk of cancer are less than optimal. Although surgical procedures eliminate the risk, the mental and physical sequelae of these procedures can be substantial. Surveillance with colonoscopic biopsies is likely effective in reducing although not eliminating the risk of colorectal cancer. Efforts to develop chemopreventative agents and improved surveillance methods remain areas of active investigation.

Colon cancer: detection and prevention

Recent data have advanced our ability to detect, survey, and manage patients with colonic neoplasia. Current studies and consensus statements increasingly support the role of colonoscopic screening over less invasive testing such as FOBT or FS for appropriately selected individuals. There are many issues, however, that remain unresolved. What is the appropriate surveillance of an individual with a single family member who had colon cancer at an early age? How should family members of suspected HNPCC kindreds be managed? There has yet to be a prospective cohort validation of the Bethesda criteria in directing clinical practice, with the endpoint of mortality reduction. Questions regarding prophylaxis with dietary supplements and medications are exciting areas that are currently under study. As newer technologies become clinically available for molecular diagnostics and screening, and virtual colonoscopy with computed tomography and magnetic resonance disseminates, there will undoubtedly be new questions to be answered regarding their ability to aid in the detection and management of colon cancer.

Sclerosing cholangitis

Primary sclerosing cholangitis in children can mimic autoimmune hepatitis in the absence of inflammatory bowel disease. Most adult patients have been identified with human leukocyte antigens that either predispose or protect against disease. Novel class I alleles and cytokine polymorphisms may also contribute to disease susceptibility. Primary alpha-hemolytic streptococci infection does not appear to directly cause primary sclerosing cholangitis. Promising diagnostic modalities such as single photon emission tomography require further study in comparison with cholangiographic techniques. Positron-emission tomography and DNA cytometry appear promising for confirming occult cholangiocarcinoma when present. The chemoprevention effects of ursodeoxycholic acid on colorectal dysplasia await further investigation. Initial results from high-dose ursodeoxycholic acid in halting disease progression, however, suggest a beneficial effect. In contrast, the impact of endoscopic therapy on natural history remains unresolved. Although liver transplantation continues to be effective for end-stage liver disease, disease recurrence in the allograft is a controversial topic.

Pathologic features of early inflammatory bowel disease

Often the pathologic changes of IBD are subtle and may not be present in a proportion of biopsy specimens. In cases of early disease, the changes may be missed, and additional specimens should be taken after a period of time. Modifying factors, such as prebiopsy treatment and coexisting disease, should be considered. A forum to review cases and allow for communication between gastroenterologists and pathologists is especially useful for clinicopathologic correlation and assignment of a working diagnosis to each case. Careful attention to the pathologic features of early UC and CD would be most useful when evaluating new therapies for IBD.

Endoscopy in inflammatory bowel disease

With the heterogeneous clinical presentation of IBD, endoscopy plays an integral role in the initial diagnosis of ulcerative colitis and Crohn's disease. Although radiographic tests often are supplemental in the work-up of IBD, colonoscopy with biopsy is the test of choice if IBD is suspected and is more sensitive than radiographic tests. Endoscopic features can be helpful in differentiating ulcerative colitis and Crohn's disease. Currently the only mode for detecting dysplasia and stratifying the risk of developing colorectal cancer is through complete colonoscopy with multiple biopsy specimens. Complications of IBD can be managed effectively with endoscopic therapy. The role of endoscopic ultrasound and future developments in endoscopic therapy need to be defined by future studies.

Risk factors for ileoanal J pouch-related septic complications in ulcerative colitis and familial adenomatous polyposis

OBJECTIVE

To analyze the association between pre- and perioperative factors and pouch-related septic complications (PRSC) in ulcerative colitis (UC) and in familial adenomatous polyposis (FAP) after ileal pouch-anal anastomosis (IPAA).

SUMMARY BACKGROUND DATA

For patients with UC and FAP, IPAA is the surgical therapy of choice, but in some patients the outcome is compromised by PRSC.

METHODS

A total of 706 consecutive patients (494 UC, 212 FAP) were assessed in a study aimed at identifying subgroups of patients who were at high risk for PRSC. The rate of PRSC was analyzed as a time-dependent function (Kaplan-Meier estimation). Patients with UC and FAP were stratified separately according to associated factors (age, sex, surgeon's experience, temporary ileostomy, colectomy before IPAA, anastomotic tension, and several factors specific for UC).

RESULTS

In all, 131 (19.2%) patients had PRSC (23.4% UC, 9.4% FAP). In patients with UC, the estimated 1-year PRSC rate was 15.6% and the estimated 3-year PRSC rate was 24.2%. In patients with FAP, the estimated 1-year and 3-year PRSC rates were 9.2%. The difference between the estimated rates of PRSC was significant (P <.001). In the univariate analysis, patients with UC younger than 50 years, with severe proctitis, with preoperative hemoglobin levels less than 10 g/L, or receiving corticoid medication had a significantly higher risk for PRSC (P =.039, P =.037, P =.047, P =.003, respectively). Multivariate analysis showed that patients with UC receiving a systemic prednisolone-equivalent corticoid medication of more than 40 mg/day had a significantly greater risk of developing pouch-related complications than patients with UC receiving 1 to 40 mg/day and patients with UC who were not receiving corticoid medication (RR: 3.78, 2.25, 1, respectively, P <.001). Patients with FAP proved to have a significantly higher risk for PRSC in the univariate and multivariate analyses if anastomotic tension had occurred (RR 3.60, P =.0086).

CONCLUSIONS

Pouch-related septic complications occur as late complications and should therefore be considered in regular, specific long-term follow-up examinations. The authors identified significant risk factors for PRSC specific to patients with UC and FAP; these must be considered for each individual surgical strategy.

Ulcerative colitis

Ulcerative colitis is a chronic inflammatory disease of the rectum and colon. Results from many studies in people and animals of intestinal inflammation suggest that ulcerative colitis results from environmental factors triggering a loss of tolerance for normal intestinal flora in genetically susceptible individuals. Although progress has been made in the overall management of the disease, no innovative treatment has been developed. By contrast with Crohn's disease, there are few clinical data on biological agents. Probiotics seem the most promising of several experimental and traditional agents that have been investigated in controlled clinical trials.

Diagnostic methodologies: serology, endoscopy, and radiology

The two major inflammatory bowel diseases, Crohn's disease (CD) and ulcerative colitis (UC), represent clinicopathologic entities that traditionally have been diagnosed on the basis of a combination of clinical, radiologic, endoscopic, and histologic features. Serum perinuclear antineutrophil cytoplasmic antibodies (pANCA) and anti-Saccharomyces cerevisiae antibodies (ASCA) have recently been added to our diagnostic armamentarium. Several studies have demonstrated that UC-associated pANCAs recognize nuclear antigens. Additional studies have demonstrated that the pANCA human monoclonal antibody (mAb) Fab 5-3 reacts with histone H1 and with bacterial and mycobacterial antigens. Several reports have suggested that, in CD, pANCA and ASCA are correlated with colonic and small bowel disease respectively. One study found that higher ASCA levels were correlated with more aggressive CD. Serology may prove to be useful in predicting the evolution of indeterminate colitis. Magnetic resonance imaging (MRI) and leukocyte scintigraphy hold promise in identifying inflammatory CD. MRI enteroclysis is useful in identifying both luminal small bowel disease and extraluminal complications. A recent study of surveillance colonoscopy in extensive Crohn's colitis showed a high risk of dysplasia and cancer.