A colorectal mosaic pattern might be an endoscopic feature of collagenous colitis

Colitis nucleomigrans: The third type of microscopic colitis (part 1)

Microscopic colitis (MC), encompassing collagenous colitis and lymphocytic colitis, is featured by chronic diarrhea, normal‐looking endoscopic findings and unique microscopic appearance. After reviewing biopsied nonspecific colitis, we propose the third type of MC: colitis nucleomigrans (CN). Histopathological criteria of CN included: (i) chained nuclear migration to the middle part of the surface‐lining columnar epithelium; (ii) apoptotic nuclear debris scattered below the nuclei; and (iii) mild/moderate chronic inflammation in the lamina propria. Thirty‐three patients (M:F = 20:13; median age 63 years, range 17–88) fulfilled our criteria. Seven cases demonstrated MC‐like clinical/endoscopic features. Mucosal reddening with or without erosion/aphtha was endoscopically observed in the remaining 26 cases with inflammatory bowel disease (IBD)‐like features: occult/gross hematochezia seen in 19, abdominal pain in two and mucin secretion in two. Cleaved caspase‐3‐immunoreactive apoptotic debris appeared more frequently in IBD‐like CN than in MC‐like CN, while CD8‐positive intraepithelial lymphocytes comparably appeared in both. Proton pump inhibitors (PPIs) were administered in five (71%) cases with MC‐like features, and in three diarrhea improved after drug cessation. In IBD‐like CN cases, eight (31%) received PPIs. Four patients received chemotherapy against malignancies. Four patients associated immune‐related disorders. Microscopic appearance of CN also appeared in a remission state of ulcerative colitis (12/20 lesions).

Magnifying image-enhanced endoscopy for collagenous colitis

Background and study aims  We report a case series of 5 patients with collagenous colitis (CC) presenting with chronic watery diarrhea, who were subjected to magnifying, chromoendoscopy and narrow band imaging (NBI). Magnifying chromoendoscopy revealed whitish-clouded, honeycomb-like appearance at orifices of the crypts. NBI with high magnification revealed irregular caliber variation of the subepithelial capillary network. Presence of these features corresponded with histological characteristics of CC indicated by thickening of the subepithelial collagen layer. We concluded that magnifying image-enhanced endoscopy is a reliable tool to diagnose CC.

Endoscopic findings and colonic perforation in microscopic colitis: A systematic review

INTRODUCTION

Microscopic colitis (MC) is a clinical syndrome of severe watery diarrhea with few or no endoscopic abnormalities. The incidence of MC is reported similar to that of other inflammatory bowel diseases. The need for histological confirmation of MC frequently guides reimbursement health policies. With the advent of high-definition (HD) coloscopes, the incidence of reporting distinct endoscopic findings in MC has risen. This has the potential to improve timely diagnosis and cost-effective MC management and diminish the workload and costs of busy modern endoscopy units.

METHODS

Publications on distinct endoscopic findings in MC available until March 31st, 2017 were searched systematically (electronic and manual) in PubMed database. The following search terms/descriptors were used: collagenous colitis (CC) OR lymphocytic colitis (LC) AND endoscopy, colonoscopy, findings, macroscopic, erythema, mucosa, vasculature, scars, lacerations, fractures. An additional search for MC AND perforation was made.

RESULTS

Eighty (n=80) articles, predominantly single case reports (n=49), were found. Overall, 1582 (1159F; 61.6±14.1 years) patients (pts) with MC and endoscopic findings were reported. The majority of articles (n=62) were on CC (pts 756; 77.5% females). We identified 16 papers comprising 779 pts (69.2% females) with LC and 7 articles describing 47 pts (72.3% females) diagnosed as MC. The youngest patient was 10 and the oldest a 97-year-old. Aside diarrhea, symptoms included abdominal pain, weight loss, bloating, flatulence, edema and others. In the study group we found 615 (38.8%) persons with macroscopic lesions in gut. Isolated linear ulcerations were identified in 7 pts (1.1%) while non-ulcerous lesions i.e. pseudomembranes, a variable degree of vasculature pruning & dwindling, mucosal lacerations and abnormalities such as erythema/edema/nodularity, or surface textural alteration in 608 pts (98.1%). The location of endoscopic findings was not reported in 27 articles. The distinct endoscopic findings were described in the left (descending, sigmoid, rectum - 10/21/11 studies), right (cecum, ascending - 7/7 studies), transverse colon (n=12), as well as duodenum (n=4), and terminal ileum (n=2). In 17 (1.1%) pts colonic perforation occurred.

CONCLUSION

Endoscopic findings are recognized with increased frequency in pts with MC. This could improve MC diagnosis by prompting a more extensive biopsy protocol in such cases and an earlier initiation of treatment. Procedure-related perforation has been reported in this group; therefore, cautious air insufflation is advisable when endoscopic findings are recognised.

Macroscopic findings in collagenous colitis: a multi-center, retrospective, observational cohort study

BACKGROUND

Collagenous colitis (CC) is by definition a histological diagnosis. However, colonoscopy often reveals characteristic endoscopic findings. The aim of this study was to evaluate the frequency and type of endoscopic findings in patients diagnosed with CC in 4 participating centers.

METHODS

This was a retrospective study; the databases of 2 university hospitals in Edinburgh (Scotland) and Malmö (Sweden), and 2 district general hospitals in Tomelloso (Spain) and Gateshead (England) were interrogated for patients diagnosed with CC between May 2008 and August 2013. Endoscopy reports and images were retrieved and reviewed; data on lesions, sedation, bowel preparation and endoscopist experience were abstracted. Categorical data are reported as mean±SD. Fischer's exact, chi-square and t (unpaired) tests were used to compare datasets. A two-tailed P-value of <0.05 was considered statistically significant.

RESULTS

607 patients (149 male, mean age 66.9±12.25 years) were diagnosed with CC. A total of 108/607 (17.8%) patients had one or more suggestive endoscopy findings: i.e., mucosal erythema/edema, 91/607 (15%); linear colonic mucosal defects, 12/607 (2%); or mucosal scarring, 5/607 (0.82%). For colonic mucosa erythema, there was no difference in the odds of finding erythema with the use of different bowel preparation methods (P=0.997). For colonic mucosal defects there was some evidence (P=0.005) that patients colonoscoped by experienced endoscopists had 87% less odds of developing such defects. Moreover, there was evidence that analgesia reduced the odds of developing mucosal defects by 84%.

CONCLUSION

A significant minority of patients with CC have endoscopic findings in colonoscopy. The description of such findings appears to be related to the endoscopist's experience.

Drug-induced inflammatory bowel disease and IBD-like conditions

The pathogenesis of inflammatory bowel disease (IBD) is multifactorial and results from an interaction between genetic, immunologic, microbial, and environmental factors. Certain drugs could act as a trigger for the disease and have been implicated in the development of new onset IBD in a number a studies. These relationships are based on case reports and cohort studies, as proving this in the context of randomized controlled trials would be difficult. Drugs that have been linked to causing or worsening IBD include isotretinoin, antibiotics, nonsteroidal antiinflammatory drugs, oral contraceptives, mycophenolate mofetil, etanercept, ipilimumab, and rituximab. Bowel preparation for colonoscopy has also been associated with aphthoid lesions that may be confused with IBD. However, given the source of these reports we have to be cautious in the interpretation of the data before concluding that these drugs trigger IBD and what is being observed is not related to other confounding factors. Different pathogenic mechanisms have been suggested for the different drugs listed above. In order to clarify the confusion a comprehensive literature review was performed with the goal of advancing the knowledge on this subject.

An epidemiological study of collagenous colitis in southern Sweden from 2001-2010

AIM: To estimate the incidence of collagenous colitis (CC) in southern Sweden during 2001-2010.

METHODS: Cases were identified by searching for CC in the diagnostic registers at the Pathology Departments in the county of Skåne. The catchment area comprised the south-west part of the county (394 307 inhabitants in 2010) and is a mixed urban and rural type with limited migration. CC patients that had undergone colonoscopy during the defined period and were living in this area were included in the study regardless of where in Skåne they had been diagnosed. Medical records were scrutinized and uncertain cases were reassessed to ensure that only newly diagnosed CC cases were included. The diagnosis of CC was based on both clinical and histopathological criteria. The clinical criterion was non-bloody watery diarrhoea. The histopathological criteria were a chronic inflammatory infiltrate in the lamina propria, a thickened subepithelial collagen layer ≥ 10 micrometers (μm) and epithelial damage such as flattening and detachment.

RESULTS: During the ten year period from 2001-2010, 198 CC patients in the south-west part of the county of Skåne in southern Sweden were newly diagnosed. Of these, 146 were women and 52 were men, i.e., a female: male ratio of 2.8:1. The median age at diagnosis was 71 years (range 28-95/inter-quartile range 59-81); for women median age was 71 (range 28-95) years and was 73 (range 48-92) years for men. The mean annual incidence was 5.4/10⁵ inhabitants. During the time periods 2001-2005 and 2006-2010, the mean annual incidence rates were 5.4/10⁵ for both periods [95% confidence interval (CI): 4.3-6.5 in 2001-2005 and 4.4-6.4 in 2006-2010, respectively, and 4.7-6.2 for the whole period]. Although the incidence varied over the years (minimum 3.7 to maximum 6.7/10⁵) no increase or decrease in the incidence could be identified. The odds ratio (OR) for CC in women compared to men was estimated to be 2.8 (95% CI: 2.0-3.7). The OR for women 65 years of age or above compared to below 65 years of age was 6.9 (95% CI: 5.0-9.7), and for women 65 years of age or above compared to the whole group the OR was 4.7 (95% CI: 3.6-6.0). The OR for age in general, i.e., above or 65 years of age compared to those younger than 65 was 8.3 (95% CI: 6.2-11.1). During the last decade incidence figures for CC have also been reported from Calgary, Canada during 2002-2004 (4.6/10⁵) and from Terrassa, Spain during 2004-2008 (2.6/10⁵). Our incidence figures from southern Sweden during 2001-2010 (5.4/10⁵) as well as the incidence figures presented in the studies during the 1990s (Terrassa, Spain during 1993-1997 (2.3/10⁵), Olmsted, United States during 1985-2001 (3.1/10⁵), Örebro, Sweden during 1993-1998 (4.9/10⁵), and Iceland during 1995-1999 (5.2/10⁵) are all in line with a north-south gradient, something that has been suggested before both for CC and inflammatory bowel disease.

CONCLUSION: The observed incidence of CC is comparable with previous reports from northern Europe and America. The incidence is stable but the female: male ratio seems to be decreasing.

Biopsy interpretation of colonic biopsies when inflammatory bowel disease is excluded

The interpretation of colonic biopsies related to inflammatory conditions can be challenging because the colorectal mucosa has a limited repertoire of morphologic responses to various injurious agents. Only few processes have specific diagnostic features, and many of the various histological patterns reflect severity and duration of the disease. Importantly the correlation with endoscopic and clinical information is often cardinal to arrive at a specific diagnosis in many cases.

Distinct colonoscopy findings of microscopic colitis: Not so microscopic after all?

Microscopic colitis (MC) is considered an “umbrella term”, comprising two subtypes, i.e., collagenous colitis (CC) and lymphocytic colitis (LC). They are classically associated with normal or unremarkable colonoscopy. In the last few years, reports have been published revealing findings that are thought to be characteristic or pathognomonic of MC, especially CC. A systematic electronic and manual search of PubMed and EMBASE (to December 2010), for publications on distinct endoscopic findings in MC, resulted in 42 relevant reports for inclusion in this review. Eighty eight patients with collagenous colitis were presented. Only one publication describing a distinct endoscopic pattern in LC was found. Typical findings in CC are alteration of the vascular mucosal pattern, mucosal nodularity, a sequence of change from mucosal defects to mucosal cicatricial lesions, and perhaps (although of doubtful relevance) mucosal pseudomembranes. A causal connection of mucosal defects with the use of lansoprazole seems to exist. Adoption of the proposed lesion description herein is recommended in order to improve homogeneity of future reports.