Expression of colonic antigens by goblet and columnar epithelial cells in ileal pouch mucosa: their association with inflammatory change and faecal stasis.

AIMS--To investigate colonic metaplasia of goblet and columnar epithelial cells in ileal pouch mucosa; to correlate this with the degree of morphological and inflammatory change; and to assess whether such changes are related to the presence of faecal stasis. METHODS--Biopsy specimens of ileal pouch mucosa were taken from 31 patients (30 with ulcerative colitis, one with familial adenomatous polyposis) either before (eight patients) or after (23 patients) ileostomy closure. A simple morphological technique was used to assess changes in villous height. Inflammatory change was estimated using an established scoring system for pouchitis, and acquisition of colonic antigens was determined by immunohistochemistry using three monoclonal antibodies which recognise components of the two major epithelial cell types in the colorectum. The degree of staining with the monoclonal antibodies was graded and the grades correlated with an index of villous atrophy and with the inflammatory scores. RESULTS--Five of eight (63%) pre-closure and 15 of 23 (65%) post-closure biopsy specimens showed increased staining with an antibody against components of columnar epithelial cells. One of eight (12%) pre-closure and 15 of 23 (65%) post-closure biopsy specimens stained with an antibody for colonic mucin. Although both types of staining showed a positive correlation with the pouchitis score, they also occurred in the absence of inflammation. CONCLUSIONS--Both goblet and columnar cells acquire colonic characteristics which are incomplete, but may represent a true adaptive response as they can develop in the absence of inflammation. As the change in goblet cells occurs after ileostomy closure, faecal stasis is likely to be a major contributory factor. Changes in columnar cells may occur before ileostomy closure in the absence of faecal stasis.     

Mucin expression in the ileoanal reservoir reflects incomplete mucosal adaptation

Restorative proctocolectomy is regarded as a standard surgical procedure for patients who require a proctocolectomy for ulcerative colitis and familial adenomatous polyposis. The ileal mucosa undergoes colonic phenotypic change with time, but the extent and relevance of these changes to the long-term safety of the ileoanal pouch are unclear. The aim of this study was to study the mucin biology of this adaptive process in order to assess its extent and possible impact on pouch safety. Ileoanal pouch biopsies from a cohort of patients and normal ileal and colonic controls were subjected to histological, biochemical, histochemical, and immunohistochemical mucin analysis. Mucin sulphation and sialic acid O-acetylation were studied as parameters of colonic phenotypic change. Fifty-one patients, 16 ileal, and 22 colonic controls were studied. Seventy per cent of biopsies retained villous mucosal architecture, with no cases of dysplasia detected. Ileoanal pouch mucosal sulphation and sialic acid O-acetylation did not reach colonic levels, thus indicating limited evidence for a more colonic phenotype. The data from this study suggest that colonic phenotypic change within the ileoanal reservoir is incomplete, with no cases of dysplasia detected. The degree of phenotypic change is less than in previous studies, which may support, but not prove, our hypothesis that there may be a process of reversion to an ileal type mucosa in the ileoanal reservoir with time.     

Qualitative assessment and morphometry in the study of the ileal reservoir after restorative proctocolectomy

Little is known about the long-term effects on the reservoir mucosa in patients with ulcerative colitis and familial polyposis coli who undergo proctocolectomy with subsequent construction of ileal reservoir/pouch and ileoanal anastomosis. In these patients, questions regarding adaptation towards a more colon-like mucosa and/or development of (pre)malignant changes are of particular importance. With the aim of designing a method for reliable evaluation of the mucosa in the ileal pouch, biopsies from 10 patients were studied by semiquantitative assessment and morphometry. The findings were compared with those obtained from normal jejunum, ileum, and colon. The following parameters were found to be important: Villous surface density, quantity of goblet cells, number of mitoses, and the presence/absence of predominantly sulphated mucin+ goblet cells. The number of Paneth cells did not show significant changes. The villous surface density was determined by a cycloid test system applied to vertical sections. Semiquantitative assessment was a sufficiently precise method for the evaluation of the quantity of goblet cells. The counting of sulphated mucin+ goblet cells was not reproducible, instead a simple statement about the presence or absence of these cells was judged to be adequate. The number of mitoses and of Paneth cells were counted directly. During the first year of function the ileal pouch showed signs of adaptation towards a colon-like mucosa: Reduction of villous surface density, increased mitotic activity, and appearance of sulphated mucin+ goblet cells. The number of Paneth cells did not show significant changes. The amount of goblet cells was generally not increased, rather reduced in some patients.     

Colonic aberrant crypts in children with familial adenomatous polyposis

Aberrant crypt foci of the colonic mucosa have been reported in adults. The alteration may be defined macroscopically or histologically and may or may not be combined with adenomatous changes. Aberrant crypt foci have been regarded as precancerous lesions and are more common in patients with familial adenomatous polyposis. The present report describes the presence of many histologically recognizable aberrant crypt foci without adenomatous changes in the colonic mucosa of 3 children with familial adenomatous polyposis. The openings of the aberrant crypt foci contained inspissated granulofilamentous mucus. Additionally, this report documents the presence of a peculiar serrated appearance of the mucosae surface outline of the nonadenomatous areas. This appears to result from elongation of the crypts and dilated openings/micropapillary arrangement of the uppermost part of the walls of the crypts, with a thin intervening stroma. Neither of these findings has been reported previously to occur in children. They may represent the earliest histologically identifiable changes ever recorded in the colon of patients with familial adenomatous polyposis.     

Mucin secretion and morphological changes of the mucosa in non-neoplastic diseases of the colon

Changes in mucin secretion and increase in height of the colonic mucosa adjacent to colorectal carcinoma (transitional mucosa) have been considered pre-malignant. In this study similar changes (both morphological and histochemical) have been found in some cases of ulcerative colitis and ischaemic colitis, as well as in juvenile, inflammatory and hyperplastic (metaplastic) polyps. 'Transitional' patterns of mucin secretion also occur in some other cases of ulcerative colitis, colostomies and Crohn's disease of the colon in which the mucosa has a normal height, suggesting the changes in mucin secretion are independent of mucosal morphology. In all these pathological conditions, hyperplastic (metaplastic) mucosa also coexisted. These findings seem to suggest that: (1) 'transitional' changes more likely represent a secondary regenerative phenomenon rather than a premalignant one; (2) the pattern of mucin secretion is not selective enough to serve as a premalignant marker; therefore is not a valid prognostic indicator in colonic biopsies; (3) hyperplastic (metaplastic) changes might derive from 'transitional' mucosa as a result of a more mature phase of this exaggerated regenerative phenomenon. However, in some patients longstanding 'transitional' mucosa may lead to dysplasia under the influence of environmental and genetic factors.     

Iliac mucosa changes in late periods after total colectomy in patients with syndromes of gastro-intestinal polyposis

We studied follow-up iliac mucosa biopsies from 11 patients with juvenile polyposis and 4 patients with familial adenomatous polyposis who had undergone total colectomy with mucosal proctoectomy with creation of straight ileoanal anastomosis. The biopsies that have been taken from the posterior wall of the terminal ileum show incomplete and focal neocolonic transformation of iliac mucosa. Nevertheless, in most cases iliac mucosa preserved its architectural and histochemical characteristics. Chronic inflammation in iliac mucosa is not typical for patients with polyposis.     

Restorative proctocolectomy: operative safety and functional outcomes

Restorative proctocolectomy (total proctocolectomy and ileal J pouch anal anastomosis) has been accepted as the operation of choice in the setting of chronic ulcerative colitis and familial adenomatous polyposis. The purpose of this study was to assess operative safety and functional outcome after restorative proctocolectomy. A total of sixteen patients underwent surgery between January 1996 and December 1999. Hand sewn anastomosis with diverting ileostomy was performed in 9 patients and double stapled anastomosis in 7 patients. The underlying disease was ulcerative colitis in 9 cases and familial adenomatous polyposis in 7. Postoperative complications developed in 8 cases (50%), and intestinal obstruction was found in 4 cases (2 cases were operated upon). Anastomosis related complications were stenosis (n=2), leak (n=1) and perianal abscess (n=1). All patients were followed up at the outpatient clinic using questionnaires, with a mean follow up period of 19.9 months. The frequency of bowel movement was 8.2 per day in hand sewn anastomosis (HS), and 12 per day in double stapled anastomosis (DS) 3 months after surgery (period 1). This frequency decreased to 5.5 per day in HS, and 4.6 per day in DS after one year (period 2). Day and night continence was shown in 12/15, and 5/15, respectively in period 1, but improved to 10/11, and 10/11, respectively in period 2. Night time incontinence was noted in 10 of 15 patients in period 1 (seepage 3/15, soiling 7/15). The need to take anti-diarrheal medication, and to use a pad was noted in 2/15, and 10/15, respectively in period 1, but no patient took antidiarrheal medication or wore a protective pad in period 2. Postoperative urinary function was satisfactory in 13/14 patients. Postoperative sexual function was analyzed in a total of 8 patients, who showed good erection (5/5), ejaculation (5/5) and satisfactory sexual life (5/5). In females, 3 patients showed a satisfactory sexual life. In conclusion, restorative proctocolectomy for chronic ulcerative colitis and familial adenomatous polyposis can be performed safely with excellent functional outcomes, including bowel movement, urinary and sexual functions one year after surgery.     

Lipomatosis coli,a mimicker of familial polyposis

Multiple intestinal lipomas (lipomatous polyposis) are quite rare, and they can be quite challenging to diagnose because this condition may be clinically confused with familial adenomatous polyposis with a suggestive family history. Herein, we present a case of lipomatous polyposis that was presented with abdominal pain and, in colonoscopy, had more than 100 polyps. The patient was admitted for surgery with diagnosis of familial polyposis. Resected colon specimen had multiple polyps ranging from 0.1 to 1.5 cm. Microscopically, the polyps were composed of mature adipose tissue with normal overlying mucosa. There were also increased fat cells in the submucosa of the colon adjacent to the polyps. Lipomatous polyposis rarely occurs and can be confused with familial polyposis. Polypectomy is a simple and cost-effective procedure to help in diagnosis and prevent a major surgery.     

Detection of epithelial apoptosis in pelvic ileal pouches for ulcerative colitis and familial adenomatous polyposis

Background  

Ileal pouch-anal anastomosis (IPAA) is the surgical procedure of choice for patients with refractory ulcerative colitis (UC) and for familial adenomatous polyposis (FAP) with many rectal polyps. Pouchitis is one of the more frequent complications after IPAA in UC patients; however, it is rare in FAP.     

Sialomucins in the assessment of dysplasia and cancer-risk patients with ulcerative colitis treated with colectomy and ileo-rectal anastomosis

The clinical notes and histology of 374 patients treated by colectomy and ileo-rectal anastomosis for ulcerative colitis were reviewed. Only those with definite diagnosis of ulcerative colitis and follow-up rectal biopsies were included (171 cases). Morphology and patterns of mucin secretion were investigated to assess whether abnormal mucin with predominance of sialomucins is a useful indicator of malignancy-risk. Carcinoma has developed in six patients and 'precancer' in seven. The results show coexistence of dysplasia and sialomucin even in the absence of inflammation in all but three biopsies; in contrast the presence of both dysplasia and normal mucin profile was found in less than 1%. A significant correlation was noted between an inflamed mucosa and the development of cancer or precancer, the presence of sialomucins and the appearance of dysplasia. Sialomucins showed a greater sensitivity in detecting cancer than dysplasia (75% versus 30%). However, dysplasia was notably more specific (94% compared with 50%), hence its greater predictive value as indicator of malignancy (50% as against 15% for a positive sialomucin result). Mucin stains on routine fixed paraffin-embedded tissue provide a simple screening method to sharpen the assessment of dysplasia and cancer-risk in patients with ulcerative colitis despite the limitations referred to above. The lack of definite evidence of dysplasia in four patients who developed malignancy without premalignant changes in the rectal biopsies emphasises the need for frequent multiple biopsies in patients with an ileo-rectal anastomosis for ulcerative colitis.     

Galectin-3 expression in pouchitis in patients with ulcerative colitis who underwent ileal pouch-anal anastomosis (IPAA)

Galectin-3, an endogenous pleiotropic beta-galactoside-binding protein, which is expressed by various malignant and normal cells, regulates many biological and pathological processes, including inflammation. In the present study, we tested a possible correlation between the severity of pouchitis in patients with ulcerative colitis who underwent ileal pouch-anal anastomosis (IPAA) and the presence of galectin-3⁺ macrophages in pouch mucosa.     

Abnormal distribution of c-myc oncogene product in familial adenomatous polyposis.

Monoclonal antibodies raised by synthetic peptide immunisation were used to determine the distribution of the protein product of the c-myc gene by immunocytochemical staining of archival wax embedded material from patients with familial adenomatous polyposis. Polyps from 18 cases of familial adenomatous polyposis, 10 of whom had developed malignant change, and 30 normal control colonic biopsy specimens were examined. A consistent staining pattern was observed in normal mucosa; nuclear staining in the basal proliferative zone; mixed nuclear and cytoplasmic staining in the maturation zone; and cytoplasmic localisation in the surface mature zone. In contrast, the polyps and carcinomata showed a mixed pattern of cytoplasmic and nuclear localisation in the basal proliferative zone with nuclear persistence throughout the crypts to the surface mature zone. This abnormal distribution of the c-myc oncogene product may have a role in the evolution of polyps and their subsequent malignant transformation into familial adenomatous polyposis.     

Spotlight on VSL#3 Probiotic Mixture in Chronic Inflammatory Bowel Diseases

VSL#3 (VSL#3) is a high-concentration probiotic preparation of eight live freeze-dried bacterial species that are normal components of the human gastrointestinal microflora, including four strains of lactobacilli (Lactobacillus casei, L. plantarum, L. acidophilus, and L. delbrueckii subsp. bulgaricus), three strains of bifidobacteria (Bifidobacterium longum, B. breve, and B. infantis), and Streptococcus salivarius subsp. thermophilus. Data from noncomparative trials suggest that VSL#3 has clinical potential in the treatment of active mild to moderate ulcerative colitis and as maintenance therapy for patients with ulcerative colitis in remission. In addition, a randomized, open-label, multicenter trial showed that VSL#3 in combination with low-dose balsalazide (a prodrug of mesalazine [mesalamine; 5-aminosalicylic acid]) was more effective than standard doses of basalazide or mesalazine monotherapy in the treatment of acute mild to moderate ulcerative colitis. Randomized, double-blind, placebo-controlled studies have shown VSL#3 is effective in preventing the onset of acute pouchitis in patients with newly formed surgical pouches, and in maintaining remission following antibacterial treatment of acute pouchitis in patients with a history of refractory or recurrent pouchitis. Treatment guidelines from the US and the UK include VSL#3 as a therapeutic option for the prevention of pouchitis relapse in patients with chronic pouchitis. In general, VSL#3 was well tolerated in clinical trials. Large, well designed, controlled confirmatory clinical trials will further determine the place of VSL#3 in the treatment of ulcerative colitis.     

Juvenile polyposis coli: a facultative precancerosis with some similarities to ulcerative colitis?

We investigated the case of a 13-year-old male with juvenile polyposis (JP) to determine the extent of intraepithelial neoplasia and associated genetic changes, as well as cellular proliferation, within these polyps using immunohistochemistry with antibodies against p53, bcl-2, and Ki-67. Examination of the total proctocolectomy specimen revealed 70 polyps. The 18 largest polyps were investigated microscopically and disclosed the typical hamartomas with frequent erosions of the surface epithelium and reparative changes. Only one polyp showed focal low-grade intraepithelial neoplasia. The immunohistochemical studies revealed an expression of p53 and an abnormal Ki-67 pattern of the surface epithelium only within the neoplastic area. These findings may hint at a possible pathogenetic mechanism for the evolution of colorectal cancer in JP. As in ulcerative colitis, carcinomas in JP may develop along a dysplasia-carcinoma sequence resulting from permanent mechanical insults, inflammation, and repair rather than from an adenoma-carcinoma sequence as in familial adenomatous polyposis (FAP).     

Involvement of the appendix in the inflammatory process in severe nonspecific chronic ulcerative colitis in children

The authors examined appendix tissues taken from 16 children and adolescents who had undergone colectomy for severe chronic ulcerative colitis. Fourteen patients had the mucosa and submucous layer involved in the chronic inflammatory process that is typical of ulcerative colitis, 5 patients showed inflammation in the muscular and subserous layers. The clinical symptomatology of appendicitis was absent.     

Mucin depletion in inflammatory bowel disease.

The mucin and gland content of 26 rectal biopsy specimens--five normal specimens, 10 from patients with ulcerative colitis, and 11 from patients with Crohn's disease--were measured using a Quantimet image analyser. There was significantly less mucin in the groups with ulcerative colitis compared with either those with Crohn's disease or the normal controls. The difference in the gland content between the groups with ulcerative colitis and Crohn's disease and between the group with Crohn's disease and the normal controls did not reach significance. The results suggest that it is worth while assessing the mucin content of rectal biopsy specimens from patients with inflammatory bowel disease. In routine practice this assessment can be made by eye using a suitably stained section.     

Biochemical analysis of enzymic markers of inflammation in rectal biopsies from patients with ulcerative colitis and Crohn''s disease.

Rectal biopsies were collected from control subjects, patients with ulcerative colitis both active and quiescent, and from patients with Crohn's disease, both with and without rectal involvement, as judged by histological assessment. Tissue homogenates were assayed for neutrophil (vitamin B12 binding protein, myeloperoxidase, lysozyme) and lymphocyte (5' nucleotidase) selective markers. Patients with acute but not those with quiescent colitis had striking increases of the neutrophil markers. Neither patient group with ulcerative colitis showed a change in the lymphocyte marker enzyme activity. Patients with Crohn's disease involving the rectum showed significant, but less marked, increases in the activity of the neutrophil markers that were found in active ulcerative colitis. Patients with Crohn's disease, not involving the rectum, showed normal or reduced levels of neutrophil markers. Patients with Crohn's disease, both those with and without rectal involvement, had increased activities of the lymphocyte selective marker. This distinguishes this inflammatory response from that of ulcerative colitis and provides further biochemical evidence of abnormalities in apparently uninvolved mucosa from Crohn's patients.     

Expression of carcinoembryonic antigen, T-antigen, and oncogene products as markers of neoplastic and preneoplastic colonic mucosa

Several crypt abnormalities have been demonstrated in the mucosa of neoplastic and preneoplastic lesions of the large intestine. In addition, certain tumor markers are expressed in large intestinal carcinoma but not in normal mucosa. To determine whether any correlation exists between tumor marker expression and crypt abnormalities and at what stage markers are expressed, we studied specimens of large intestinal mucosa from 13 patients with preneoplastic conditions (adenomatous polyp, familial polyposis, Crohn's disease, and ulcerative colitis). The tumor markers examined include carcinoembryonic antigen (CEA), the ras gene products p21 and p21ser (mutated form), and beta-D-galactosyl-(1----3)-alpha-N-acetyl-D-galactosamine (gal--gal NAc, also known as T-antigen). Results were compared to those of five cases of adenocarcinoma of colon and three control cases of colonic mucosa obtained at immediate autopsy. All four markers were expressed in three of the five cases of adenocarcinoma, but none were expressed in the control cases. Variable expression of each marker was demonstrated in the dilated, distorted crypts of preneoplastic lesions. CEA and gal--gal NAc appeared to be expressed most frequently, suggesting that these are common markers or are expressed at an earlier stage in the neoplastic process than p21 or p21ser. Demonstration of such markers in preneoplastic conditions may be of use in determining the malignant potential and in monitoring these lesions.     

Molecular genetic analysis of exons 1 to 6 of the APC gene in non-polyposis familial colorectal cancer

Familial adenomatous polyposis coli is caused by constitutional mutations in the APC gene. The hallmark of familial adenomatous polyposis coli is the presence of numerous (>100) colorectal polyps, but mutations in the 5' end of the APC gene have been associated with familial colorectal cancer without florid polyposis. Although familial adenomatous polyposis coli accounts for only a minority of familial colorectal cancer cases, we hypothesised that APC mutations which were not associated with florid polyposis might make a significant contribution to nonpolyposis familial colorectal cancer. To investigate this possibility, we analysed 40 unrelated patients with familial colorectal cancer without classical familial adenomatous polyposis coli for mutations in exons 1 to 6 (codons 1 to 243) of the APC gene. No mutations were detected, but a C→T polymorphism at nucleotide 333 (Arg→Trp at codon 99) was identified. No 5' APC mutations were detected in two patients with desmoid tumours and a family history of colorectal cancer and polyps. We conclude that mutations in exons 1 to 6 of the APC gene are infrequent in patients with familial colorectal cancer who do not have many colorectal polyps.