Clinical Implications of Microscopic Colitis Isolated to Polyps

Microscopic colitis is generally identified on random colon biopsies performed for chronic diarrhea, but rarely incidental polyps have histologic features of microscopic colitis. We compared patients with polypoid microscopic colitis to control patients with conventional polyps to determine the implications of polypoid microscopic colitis.

Medical records were searched for patients without prior or concurrent microscopic colitis who were found to have polypoid microscopic colitis. For each patient with polypoid microscopic colitis, one patient with conventional polyps was selected as a control. We reviewed the histologic features of each polypoid microscopic colitis specimen, and evaluated endoscopic and clinical findings for polypoid microscopic colitis patients and controls.

Twenty-six patients with polypoid microscopic colitis were identified with histologic features of collagenous colitis in 8 patients (31%) and lymphocytic colitis in 18 patients (69%). Polypoid microscopic colitis was unifocal in 14 patients (54%) and multifocal in 12 patients (46%). Patients with polypoid microscopic colitis were older than control patients (median age = 60 years vs 66 years, P = .04). On follow-up 7 patients with polypoid microscopic colitis (33%) developed chronic diarrhea compared to 3 (12%) controls (P = .16). Of patients with follow-up biopsies, 1 patient with polypoid microscopic colitis (13%) and no control patients developed microscopic colitis (P = 1).

Polypoid microscopic colitis may be identified in asymptomatic patients and most patients do not develop chronic diarrhea, but some patients with polypoid microscopic colitis develop diarrhea (33% vs 12% in controls) or conventional microscopic colitis on follow-up. Thus pathologists should distinguish polypoid microscopic colitis from conventional microscopic colitis but may inform clinicians of the uncertain association with chronic diarrhea to guide decisions regarding follow-up.

Frequency And Risk Factors Of Microscopic Colitis As A Cause Of Chronic Watery Diarrhoea

BACKGROUND

Microscopic colitis (MC) is one of the most underdiagnosed conditions leading to chronic watery diarrhoea in patients worldwide. This is the first study of this kind in Pakistan and we aimed to calculate the frequency as well as study the risk factors behind the disease.

METHODS

This was a prospective cross-sectional study in a tertiary care hospital in Pakistan. A total of 58 participants with chronic watery diarrhoea who had normal colonoscopy were recruited for the study and biopsies were obtained for diagnosing MC.

RESULTS

2 participants out of 58 (3.4%) had biopsy proven microscopic colitis; one patient had a lymphocytic colitis variant and the other had a collagenous colitis variant. The average score based on the MC scoring system was 7.53 in the entire study group. The patient with lymphocytic colitis had a score of 06 while the patient with collagenous colitis had a score of 8.

CONCLUSIONS

The frequency of microscopic colitis was found to be 3.4% of all cases of chronic watery diarrhoea. A link between MC and autoimmune diseases was also observed. However, we had a limited sample size and encouraged future studies to employ a larger sample size to get a multifaceted look at the disease process.

Dietary Calcium and Risk of Microscopic Colitis

BACKGROUND

Microscopic colitis (MC) is an increasingly common cause of watery diarrhea particularly in older individuals. The role of diet in MC has received little study.

METHODS

We conducted a case-control study at a single institution enrolling patients referred for elective outpatient colonoscopy for diarrhea. Patients were classified as cases with MC or non-MC controls after a review of colon biopsies by 1 research pathologist. Study subjects were interviewed by a trained telephone interviewer using a validated food frequency questionnaire. Adherent microbes were evaluated from colonic biopsies using 16s rRNA sequencing.

RESULTS

The study population included 106 cases with MC and 215 controls. Compared with controls, the cases were older, better educated, and more likely to be female. Cases with MC had lower body mass index and were more likely to have lost weight. Subjects in the highest quartile of dietary calcium intake had a lower risk of MC compared with those in the lowest quartile (adjusted odds ratio 0.22, 95% confidence interval 0.07-0.76). The findings were not explained by dairy intake, body mass index, or weight loss. We found that dietary calcium intake had significant associations with the abundance of Actinobacteria and Coriobacteriales in the microbial community of colonic biopsies.

DISCUSSION

Compared with patients with diarrhea, cases with MC had a lower intake of dietary calcium. Diet can be associated with alterations in the gut microbiota and with luminal factors that could affect the risk of MC.

Tofacitinib for celiac disease and microscopic colitis: killing two birds with one stone

Microscopic colitis is a chronic inflammatory condition of the colon. Firstline treatment consists of budesonide, with the consideration of biological agents in refractory cases. Celiac disease is a chronic immune mediated and gluten-induced enteropathy, with treatment consisting of a gluten-free diet. There is an association between microscopic colitis and instead of xand celiac disease, especially in refractory cases they can coincide. In this manuscript, we report for the first time the efficacy of tofacitinib, a pan Janus kinase inhibitor, in the treatment of concomitant microscopic colitis and celiac disease, resulting in persistent clinical and histological remission.

Microbial Associations With Microscopic Colitis

INTRODUCTION

Microscopic colitis is a relatively common cause of chronic diarrhea and may be linked to luminal factors. Given the essential role of the microbiome in human gut health, analysis of microbiome changes associated with microscopic colitis could provide insights into the development of the disease.

METHODS

We enrolled patients who underwent colonoscopy for diarrhea. An experienced pathologist classified patients as having microscopic colitis (n = 52) or controls (n = 153). Research biopsies were taken from the ascending (ASC) and descending (DES) colon, and the microbiome was characterized with Illumina sequencing. We analyzed the associations between microscopic colitis and microbiome with a series of increasingly complex models adjusted for a range of demographic and health factors.

RESULTS

We found that alpha diversity was significantly lower in cases with microscopic colitis compared with that in controls in the DES colon microbiome. In the DES colon, a series of models that adjusted for an increasing number of covariates found taxa significantly associated with microscopic colitis, including Proteobacteria that was enriched in cases and Collinsella that was enriched in controls. While the alpha diversity and taxa were not significantly associated with microscopic colitis in the ASC colon microbiome, the inference P values based on ASC and DES microbiomes were highly correlated.

DISCUSSION

Our study demonstrates an altered microbiome in cases with microscopic colitis compared with that in controls. Because both the cases and controls experienced diarrhea, we have identified candidate taxa that could be mechanistically responsible for the development of microscopic colitis independent of changes to the microbial community caused by diarrhea.

Gastrointestinal Conditions: Inflammatory Bowel Disease

Inflammatory bowel diseases (IBDs) comprise a group of conditions thought to be caused by a dysregulated host immune response to the gut microbiome. IBDs, which affect 1.3% of Americans, include Crohn disease (CD), ulcerative colitis (UC), and microscopic colitis. UC and microscopic colitis are limited to the colon, but CD can occur anywhere along the gastrointestinal tract. Gastrointestinal symptoms typically predominate, including diarrhea and abdominal pain, along with systemic symptoms of weight loss, fatigue, night sweats, and fever. However, many patients have extraintestinal symptoms, often in the joints, skin, or eyes; extraintestinal symptoms can appear before gastrointestinal symptoms. Colonoscopy with biopsy is the test of choice for diagnosing UC and microscopic colitis. Diagnosing CD typically requires ileocolonoscopy and also may require esophagogastroduodenoscopy. Traditionally, therapy involved mesalamine for UC, thiopurines or methotrexate for CD, and budesonide for microscopic colitis. However, recently, biologic drugs targeting tumor necrosis factor alpha and other inflammatory drugs have revolutionized care of IBD. Surgery (complete resection of involved colon) can be curative in UC. In CD, surgery typically is only used for complications or refractory disease.

Analysis of Clinical and Histopathological Findings in Microscopic Colitis

OBJECTIVE

Microscopic colitis is a chronic inflammatory disorder characterized by a triad of chronic diarrhea, endoscopy without significant abnormality, and distinct histopathological features. Histopathologically, microscopic colitis is divided into 3 subtypes; collagenous colitis, lymphocytic colitis, incomplete microscopic colitis. The main purpose of this study was to analyze the detailed clinicopathological parameters of microscopic colitis cases in the Turkish population.

MATERIAL AND METHOD

The clinicopathological parameters were evaluated in 53 microscopic colitis cases (37 collagenous colitis, 7 lymphocytic colitis, 9 incomplete microscopic colitis) diagnosed between 2010 and 2019.

RESULTS

All cases had lymphoplasmacytosis. The presence of ≥20 eosinophils/high power field in the lamina propria was remarkable in 75.7%, 57.1%, and 11.1% of collagenous colitis, lymphocytic colitis, and incomplete microscopic colitis cases, respectively. One of the striking findings was the presence of concomitant Celiac disease in 29% of the lymphocytic colitis cases. In terms of drug use, proton pump inhibitors and nonsteroidal anti-inflammatory drugs were the most commonly used drugs.

CONCLUSION

The mean age in our series is lower than the literature and a distinct male predominance was observed in lymphocytic colitis and incomplete microscopic colitis, contrary to the literature. These suggest that susceptibility to microscopic colitis may differ between ethnic groups. The presence of overt lymphoplasmacytosis, eosinophilic infiltration and epithelial damage are the microscopic features which should alert the pathologist for the diagnosis of complete microscopic colitis. Given that microscopic colitis is a common treatable cause of chronic diarrhea, awareness of the aforementioned histopathological features is of utmost importance for accurate diagnosis and not to miss incomplete cases.

[Diagnostic utility of colonoscopy and histological evaluation in the study of patients with chronic diarrhea]

INTRODUCTION

Patients with chronic diarrhea often undergo colonoscopy evaluation, however, the performance of biopsies or ileoscopy remains controversial.

OBJECTIVE

To evaluate the usefulness of colonoscopy plus biopsies in the study of patients with chronic diarrhea.

MATERIALS AND METHODS

We retrospectively reviewed patients with chronic diarrhea who underwent colonoscopy between 2015 and 2019. Patients with incomplete data, HIV infection, abnormal endoscopic findings, colonoscopy without blind assessment, being on empiric treatment for diarrhea, and poor diagnosis were excluded. preparation. A descriptive analysis of the characteristics of the patients, histopathological findings and comparison of signs and symptoms according to histopathological finding was performed.

RESULTS

535 patients with chronic diarrhea were evaluated, of these, 283 (52.8%) underwent biopsies. In 55.1% (n=156) of the biopsies some final histopathological diagnosis was obtained. Histopathological diagnoses corresponded to ulcerative colitis (n=3), Crohn's disease (n=5), lymphocytic colitis (n=6), collagenous colitis (n=12), eosinophilic colitis (n=13), infectious colitis (n=13), Melanosis coli (n=15), nonspecific colitis (n=57) and other histological changes (n=32). Crohn's disease was only documented in biopsies of the ileum (p<0.001), ulcerative colitis was only diagnosed in biopsies of the sigmoid rectum (p=0.007), infectious colitis in its highest proportion (30.7%) was documented in biopsies of the right colon (p=0.028).

CONCLUSION

Colonoscopy and biopsies are useful in the investigation of patients with chronic diarrhea, obtaining a histological diagnosis in 55% of patients. Ileoscopy complemented colonoscopy findings to a lesser extent.

Low prevalence of colorectal neoplasia in microscopic colitis: A large prospective multi-center study

BACKGROUND AND AIMS

Microscopic colitis (MC) is the most frequent condition in subjects undergoing ileocolonoscopy for chronic non-bloody diarrhea (CNBD) in Western countries. Emerging evidence has shown a negative association between MC and colorectal cancer. Within this prospective multi-center study we have evaluated the risk of colorectal neoplasia in MC and non-MC patients with CNBD receiving ileocolonoscopy with high-definition plus virtual chromoendoscopic imaging and histopathological assessment.

METHODS

Patients with CNBD of unknown origin were prospectively enrolled in 5 referral centers in Northern Italy for ileocolonoscopy with high-definition and digital/optical chromoendoscopy plus multiple biopsies in each segment. The prevalence of colorectal neoplasia (cancer, adenoma, serrated lesion) in MC was compared to that observed in a control group including CNBD patients negative for MC, inflammatory bowel disease or eosinophilic colitis.

RESULTS

From 2014 and 2017, 546 consecutive CNBD patients were recruited. Among the 492 patients (mean age 53±18 years) fulfilling the inclusion criteria against the exclusion critieria, MC was the predominant diagnosis at histopathological assessment (8.7%: N=43, 28 CC, 15 LC). The regression model adjusted for age and gender showed a significant negative association between the diagnosis of CM and colorectal neoplasia (OR=0.39; 95% CI 0.22-0.67, p <0.001) with a 60% decreased risk of adenomatous and neoplastic serrated polyps as compared to the control group (n=412).

CONCLUSION

This multi-center study confirms MC as a low-risk condition for colorectal neoplasia. No surveillance colonoscopy program is to be performed for MC diagnosis.

Associations of Microscopic Colitis With Other Lymphocytic Disorders of the Gastrointestinal Tract

BACKGROUND & AIMS

Lymphocytic disorders of the upper and lower gastrointestinal tract seem to cluster in patients. We aimed to assess the frequency of comorbid occurrence of lymphocytic disorders in patients with microscopic colitis (MC).

METHODS

We collected data from the Miraca Life Sciences Database, a large national electronic repository of histopathologic records of patients throughout the United States. In a population of 228,506 patients who underwent bidirectional endoscopy from January 2008 through July 2016, we studied the comorbid occurrence of celiac disease, duodenal intraepithelial lymphocytosis, lymphocytic gastritis, and lymphocytic esophagitis among 3456 patients with MC. Associations were described in terms of their odds ratios (OR) and 95% CIs.

RESULTS

Any type of lymphocytic disorder occurred in 13.7% of patients with MC and 5.9% of patients without MC. The ORs of lymphocytic disorders in patients with MC were: 2.56 (95% CI, 2.32-2.82) for any type of lymphocytic disorder, 3.07 (95% CI, 1.25-7.52) for lymphocytic esophagitis, 15.05 (95% CI, 12.31-18.41) for lymphocytic gastritis, 1.73 (95% CI, 1.53-21.96) for duodenal intraepithelial lymphocytosis, and 6.06 (95% CI, 5.06-7.25) for celiac disease. Comorbidities were more common in patients with lymphocytic than collagenous colitis, with an OR of 1.74 (95% CI, 1.42-2.13). Patients with MC with comorbidities were significantly younger and had a lower proportion of men than patients with MC patients without comorbidities. Diarrhea was the predominant symptoms in all patients MC, irrespective of comorbidities.

CONCLUSION

In a retrospective study, we identified lymphocytic disorders of the upper gastrointestinal tract that are significantly more common in patients with than without MC. These associations suggest the existence of an underlying etiology that is common to all lymphocytic disorders and that affects the upper and lower gastrointestinal tract.

[Concurrent lymphocytic colitis and microscopic enteritis in patients with chronic diarrhea]

INTRODUCTION

Lymphocytic colitis and microscopic enteritis are relatively common causes of chronic diarrhea and it is characterized by an intraepithelial lymphocytic infiltrate. There have been no previous reports of coexistence between these 2 pathologies.

OBJECTIVE

To describe histological and clinical characteristic in patients with coexistence of lymphocytic colitis and microscopic enteritis.

MATERIAL AND METHODS

All cases with simultaneous diagnosis of lymphocytic duodenosis and lymphocytic colitis were reevaluated during lapse time 2010-2016 in hospital Daniel Carrion. The slides were reviewed by 3 pathologists and clinical information was obtained from clinical records. Expression of CD3 and CD8 was detected in 6 cases by immunohistochemical assays.

RESULTS

A total of 35 patients with coexistence of lymphocytic duodenitis and lymphocytic colitis were selected of the pathology archives, 80% were females, Anemia was identified in 28.5% of patients. Blastocysitis hominis infestation was identified in 31.8%. The mean intraepithelial lymphocyte CD8 and CD3 positive was 40% in microscopic enteritis, while the mean intraepithelial lymphocyte CD3 positive was 37.2% and CD8 positive was 29.2% Additionally, lymphocytic ileitis was diagnosed in 11 of our cases. Eosinophilic colitis was diagnosed in 9 cases of lymphocytic colitis Conclusion: We found that lymphocytic colitis, microscopic enteritis and even lymphocytic ileitis can coexist in a group of patients with chronic diarrhea. These findings bring the question if this concurrence of both pathologies constituted a more generalized gastrointestinal disorder, involving both the large and the small intestines.

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.

[Treatment of microscopic colitis - what's new?]

Microscopic colitis (MC) is frequent, although still uncommonly diagnosed, cause of chronic diarrhea. The etiopathology of MC is unknown but this disease has strong influence on patient's quality of life (measured by health-related quality of life - HRQoL). MC is characterized by microscopic abnormalities in large bowel's mucosa whereas endoscopic and radiological examination findings are normal. The treatment of MC is an essential social and financial problem due to its frequency in society. Thanks to the results of some controlled research which judged efficiency of some medicines as well as advisory groups recommendations, the MC therapy is nowadays going from empiric to accordance with evidence based medicine.

Irritable Bowel Syndrome and Microscopic Colitis: A Systematic Review and Meta-analysis

BACKGROUND & AIMS

Patients with microscopic colitis and patients with irritable bowel syndrome (IBS) present with similar symptoms. We examined the association between IBS and microscopic colitis in a systematic review and meta-analysis.

METHODS

We searched the medical literature to identify cross-sectional surveys or case-control studies reporting the association between microscopic colitis and IBS in 50 or more unselected adult patients. We recorded the prevalence of IBS symptoms in patients with histologically confirmed microscopic colitis, or the prevalence of histologically confirmed microscopic colitis in patients with IBS. Data were pooled using a random-effects model; the association between microscopic colitis and IBS was summarized using an odds ratio (OR) with a 95% confidence interval (CI).

RESULTS

The search strategy identified 3926 citations, of which 10 were eligible for our analysis. The pooled prevalence of IBS in patients with microscopic colitis was 33.4% (95% CI, 31.5%-40.6%), but was not significantly higher in patients with microscopic colitis than in patients with diarrhea (OR, 1.39; 95% CI, 0.43-4.47). In 3 cross-sectional surveys, the pooled OR for microscopic colitis in participants with IBS, compared with other patients with diarrhea, was 0.68 (95% CI, 0.44-1.04). In 4 case-control studies the prevalence of IBS in patients with microscopic colitis was significantly higher than in asymptomatic controls (OR, 5.16; 95% CI, 1.32-20.2).

CONCLUSIONS

Based on a meta-analysis, one third of patients with microscopic colitis reported symptoms compatible with IBS, but the prevalence of IBS was no higher than in other patients with diarrhea. The odds of microscopic colitis were no higher in patients with IBS compared with other patients with diarrhea. The value of routine colonoscopy and biopsy to exclude microscopic colitis in patients with typical IBS symptoms, unless other risk factors or alarm symptoms are present, remains uncertain.

[Chronic diarrhoea due to microscopic colitis: awareness pays]

The incidence of microscopic colitis (MC) in The Netherlands is increasing, yet the numbers are low compared to other countries. Awareness is likely to play a role. We describe two cases to illustrate the benefit of MC awareness among physicians and pathologists. In a 45-year-old female who presented with chronic diarrhoea, no cause could be identified despite extensive examinations in other hospitals. A biopsy revision, performed in our centre, revealed MC. Treatment with budesonide was immediately effective. A 76-year-old female with chronic diarrhoea was also diagnosed with MC. Because a relationship with NSAID use was suspected, the drug was withdrawn and the diarrhoea resolved. These cases illustrate that awareness of MC might accelerate the diagnosis of patients with chronic diarrhoea, consequently enabling the prescription of oral budesonide, a highly effective treatment. Some drugs are associated with an increased risk of MC. Withdrawal of these drugs could be another successful treatment strategy.

Two gastrointestinal conditions with similar symptoms and endoscopic appearance: irritable bowel syndrome and microscopic colitis

BACKGROUND/AIM

Irritable bowel syndrome (IBS) is a gastrointestinal condition characterized by chronic abdominal pain, discomfort, bloating, and alteration of bowel habits in the absence of any organic cause. This trial investigated the presence of microscopic colitis (MC) and associated factors related to MC in patients diagnosed with IBS.

MATERIALS AND METHODS

The study group (group I) consisted of 91 consecutive patients diagnosed with IBS based on the Rome III Criteria for whom colonoscopic examination was requested. The control group (group II) had 41 patients diagnosed with IBS considered as eligible for colonoscopic investigation due to specific conditions, and for whom colonoscopic examination was recommended for screening purposes due to a familial history of colon cancer. Clinical data, endoscopic findings, and the effects of the therapy were evaluated.

RESULTS

In the diarrhea-predominant IBS group, nine patients (9.89%) were diagnosed with microscopic colitis, seven with lymphocytic colitis (7.69%), and two with collagenous colitis (CC) (2.19%). None of the patients in group II were found to have MC (P = 0.007). There were no diagnoses of MC in the constipation-predominant and mixed type IBS groups.

CONCLUSION

Clinicians should keep MC in mind for patients presenting with diarrhea-predominant IBS symptoms.

[Microscopic colitis]

Microscopic colitis (MC), collagenous colitis (CC) and lymphocytic colitis (LC), represent a pathological entity causing chronic secretory diarrhea with endoscopically normal colon. Histological diagnosis is obtained by biopsies done throughout the colon. CC is defined by the thickening of the subepithelial collagen band of more than 10 pm and LC by more than 20% intraepithelial lymphocytes per epithelial cell. The incidence of MC has been steadily increasing and the prevalence of MC varies from 10-14% in patients with chronic diarrhea and endoscopically normal colon. The clinical presentation of MC is very close to that of functional diarrhea. The recent introduction of a new drug and autoimmune disease are the main factors associated with MC, and there is a special association with celiac disease is. Although rare complications can occur, MC are benign pathologies. Therapeutically, it is first necessary to eliminate a drug-induced, drug discontinuation allowing the cure of colitis, and an associated celiac disease. In other cases, budesonide is the treatment of choice for the moderate to severe forms resistant to the usual symptomatic treatments; relapse is however frequent after the withdrawal of budesonide, and may necessitate its continuation at the lower possible dose.

Genome-wide association study of celiac disease in North America confirms FRMD4B as new celiac locus

We performed a genome-wide association study (GWAS) of 1550 North American celiac disease cases and 3084 controls. Twelve SNPs, distributed across four regions (3p21.31, 4q27, 6q15, 6q25), were significantly associated with disease (p-value <1.0×10⁻⁷), and a further seven SNPs, across four additional regions (1q24.3, 10p15.1, 6q22.31, 17q21.32) had suggestive evidence (1.0×10⁻⁷ < p-value < 1.0×10⁻⁶). This study replicated a previous suggestive association within FRMD4B (3p14.1), confirming it as a celiac disease locus. All four regions with significant associations and two regions with suggestive results (1q24.3, 10p15.1) were known disease loci. The 6q22.31 and 10p11.23 regions were not replicated. A total of 410 SNPs distributed across the eight significant and suggestive regions were tested for association with dermatitis herpetiformis and microscopic colitis. Preliminary, suggestive statistical evidence for association with the two traits was found at chromosomes 3p21.31, 6q15, 6q25, 1q24.3 and 10p11.23, with future studies being required to validate the reported associations.

Microscopic colitis: clinical characteristics, treatment and outcomes in an Irish population

BACKGROUND AND AIMS

Many aspects of microscopic colitis remain poorly understood. Our aim was to report a single centre experience with this condition.

METHODS

Two hundred and twenty-two patients (52 male, 170 female; median age 64 years; range 32-90) diagnosed between 1993 and 2010 were studied. Medical notes were reviewed, and data on age, gender, clinical features, history of autoimmune diseases, medication use, cigarette smoking, histology and outcome were collected.

RESULTS

There were 99 cases of lymphocytic and 123 of collagenous colitis. Diarrhoea was almost invariably present (98 %) while abdominal pain (24 %), weight loss (10 %), faecal incontinence (8 %) and blood PR (5 %) were also described. Twenty-eight percent had concomitant autoimmune diseases, most commonly coeliac disease. Patients were taking a variety of medications at diagnosis thought to be associated with microscopic colitis including NSAIDs (22 %), aspirin (19 %), statins (15 %), proton pump inhibitors (19 %) and SSRIs (10 %) at diagnosis. Prior to the widespread use of budesonide in our institution, 33 % of patients required two or more medications during therapy compared to 15 % following the introduction of budesonide (p = 0.001). Thirty-eight percent of patients achieved spontaneous remission with either no treatment or simple anti-diarrhoeals. Using a multivariate model, the only factor associated with spontaneous remission was male gender (RR 1.9; 95 % CI 1.0-3.6; p = 0.04). Two patients had refractory microscopic colitis; one required a colectomy while a more recent case has responded to anti-TNFα therapy.

CONCLUSION

Microscopic colitis is predominantly a benign and self-limiting disorder. The introduction of budesonide has revolutionised treatment of this lesser studied inflammatory bowel disease.

Microscopic colitis and colorectal neoplastic lesion rate in chronic nonbloody diarrhea: a prospective, multicenter study

BACKGROUND

Lymphocytic and collagenous colitis are emerging as common findings in subjects undergoing colonoscopy for chronic non-bloody diarrhea (CNBD). Data concerning microscopic colitis (MC) are still limited and affected by controversial epidemiological evidences. Recent converging lines of evidence suggest that MC correlates a lower risk of colorectal neoplasia. Accordingly, we prospectively assessed MC prevalence in a multicenter cohort of subjects submitted to colonoscopy for CNBD, thereby defining whether MC influences the risk of colorectal neoplasia.

METHODS

Consecutive patients with CNBD of unknown origin underwent pan-colonoscopy with multiple biopsies. The prevalence of neoplastic patients in MC was compared with that observed in negative CNBD subjects.

RESULTS

Among 8006 colonoscopy, 305 subjects were enrolled for CNBD. Patients with CNBD were more likely to be women than men (odds ratio = 1.5; P = 0.001). Histopathology detected high prevalence of MC (16%) with a clear predominance of collagenous colitis (70%). A striking age-dependent rise in MC-associated risk was observed, depicting outstanding differences among varying age groups, as in the number needed to screen 1 new case. Gender distribution was balanced within MC patients (Female/Male = 1.5/1), especially among lymphocytic colitis (Female/Male = 1.2/1). MC patients were negatively associated with the risk of neoplastic polyps compared with negative CNBD subjects (odds ratio = 0.22; P = 0.035).

CONCLUSIONS

MC is the first cause of CNBD in subjects submitted to colonoscopy. Multiple biopsies are strongly recommended, even in the case of uneventful endoscopic inspection, especially for age ≥40 years. MC has a reduced risk of colorectal neoplasia, suggesting that this model of chronic inflammation plays a protective effect against colorectal carcinogenesis.

[Microscopic colitis is a common cause of chronic diarrhoea]

Microscopic colitis (MC) is a common cause of chronic, non-bloody diarrhoea in the elderly population. In Denmark the incidence has been rising for the last decades. Sufficient biopsy material from colon mucosa is essential for the diagnosis. Treatment is important to improve the patient's quality of life, which is significantly impaired in active MC. This paper reviews newly published data regarding epidemiology, diagnostic criteria and a new European treatment guideline and also includes updates on ongoing and future studies in MC.

A cross-sectional study of subclinical and clinical thyroid disorders in women with microscopic colitis compared to controls

BACKGROUND AND AIMS. Microscopic colitis (MC), predominantly affecting women, is associated with thyroid disorders, although purely defined of which type, or compared with controls. Its association with subclinical thyroid disorders, and related increased risk of cardiovascular diseases, has never been examined. The aim was to examine the prevalence of autoantibodies and subclinical and clinical thyroid dysfunction in female patients with MC compared with controls. METHODS. Women younger than 73 years old with biopsy-verified MC from the Department of Gastroenterology in Skåne, during 2002-2010, were invited. Out of 240 identified, 133 were finally included. A questionnaire about medical history was completed and blood samples were collected. Serum was analyzed for free thyroxin and triiodothyronine, thyroid-stimulating hormone and anti-thyroid peroxidase (anti-TPO) antibodies. A population-based group of 737 women served as controls. RESULT. The prevalence of thyroid disorders in patients was higher compared to controls [odds ratio (OR) = 2.98, 95% confidence interval (CI) = 1.78-4.99], but the prevalence of subclinical disorders was not different (OR = 1.18, 95% CI = 0.48-2.85). Anti-TPO antibodies were present in 10.6% of MC patients and 18.6% of controls. Twenty-five MC patients had hypothyroidism: 15 with Hashimoto's hypothyroidism, 6 with completed treatment of thyrotoxicosis and 4 with completed surgery after nontoxic goiter. CONCLUSION. Thyroid disorders, autoimmune hypothyroidism being most frequent, are more prevalent in patients with MC than in controls, whereas the prevalence of subclinical thyroid disorders in MC patients does not differ significantly from controls.

Diarrhoea is not the only symptom that needs to be treated in patients with microscopic colitis

BACKGROUND

Many patients with microscopic colitis (MC) also suffer from symptoms of irritable bowel syndrome (IBS), but the only treatment given is corticosteroids for the diarrhoea. The aim of this study was to examine how social factors, life style factors and drug treatment affect symptoms and well-being in patients suffering from MC.

METHODS

Women, over the age of 73years, with biopsy-verified MC, at any Departments of Gastroenterology, Skåne, between 2002 and 2010 were invited. The questionnaires Gastrointestinal Symptom Rating Scale (GSRS) and Psychological General Well-being Index (PGWB) were sent by mail, along with questions about social and life style factors, and medical history.

RESULTS

Of 240 invited, 158 patients (66%) were included (median age 63years, range 27-73years). Only 26% had never smoked. Smoking and concomitant IBS were associated with both impaired gastrointestinal symptoms (OR=3.96, 95% CI=1.47-10.66 and OR=4.40, 95% CI=2.09-9.26, respectively) and impaired psychological well-being (OR=2.77, 95% CI=1.04-7.34 and OR=3.82, 95% CI=1.83-7.99, respectively). Treatment with proton pump inhibitors (PPI) was associated with increased gastrointestinal symptoms (OR=3.44, 95% CI=1.45-8.16). Age, social factors, and corticosteroids had no effect on symptoms or well-being. Smoking was the only risk factor associated with IBS (OR=2.68, 95% CI=1.115-6.26).

CONCLUSION

Smoking and IBS are associated with impaired gastrointestinal symptoms and psychological well-being in MC patients. PPI is associated with impaired gastrointestinal symptoms.

Microscopic colitis in Uppsala health region, a population-based prospective study 2005-2009

OBJECTIVE

The aim of this study is to report on the incidence of microscopic colitis (MC), any possible relation with inflammatory bowel disease (IBD), concomitant drug consumption, related diseases and the clinical course of the diseases.

METHODS

Both new cases of IBD and MC were registered at the same time in the same geographical area. The study started in the county of Uppsala 2005-2006, and other parts of the surrounding health region were included 2007-2009. Established morphological criteria were used, i.e. a layer of subepithelial collagen band ≥ 10 μm in collagenous colitis (CC) with concomitant inflammation and at least 20 lymphocytes per 100 epithelial cells in lymphocytic colitis (LC).

RESULTS

The authors found 272 new cases of MC, 154 with CC and 118 with LC. The mean age-adjusted incidence was 7.0/1,000,000 for CC and 4.8/100,000 for LC. The clinical course was dominated by single episodes with diarrhea or intermittent symptoms, but 14% suffered from chronic diarrhea. In 10% of the cases, diagnosis was made in individuals without chronic watery diarrhea. Although not systematically tested, concomitant celiac disease was found in approximately 5% of the patients.

CONCLUSIONS

The incidence of MC in Uppsala health region is similar to other studied areas. The majority of patients had a self-limiting or easily treated condition, but 14% need a more or less continuous medication. Ten percent of the patients demonstrate other symptoms than chronic watery diarrhea. The possibility of concomitant celiac disease should be considered in new cases of MC.

[Microscopic colitis]

Microscopic colitis is characterized by chronic or intermittent watery diarrhoea. Microscopic colitis is a common cause of chronic diarrhoea in predominantly older adults. The underlying mechanism in the pathogenesis of microscopic colitis remains unspecified. Microscopic colitis including colitis collagenous, lymphocytic, microscopic colitis with incomplete findings, minimal change colitis, eosinophilic colitis, Brainerd´s diarrhoea, graft-versus-host disease, mastocytic enterocolitis and postinfectious irritable bowel syndrome. Careful consideration of the clinical features and colonic mucosal biopsies usually lead to correct diagnosis. Treatments of microscopic colitis were based primarily on case reports and personal experience. Many medications have been proposed that either offer symptomatic relief (loperamide, cholestyramine) or had anti-inflammatory or immunosuppressive properties (aminosalicylates, steroids, adalimumab, azathioprine).

Gastrointestinal symptoms and psychological well-being in patients with microscopic colitis

OBJECTIVE

Microscopic colitis (MC) and irritable bowel syndrome (IBS) are both gastrointestinal disorders with female predominance that affect well-being. Autoantibodies against gonadotropin-releasing hormone (GnRH) have recently been detected in IBS patients. The purpose of this study was to compare gastrointestinal symptoms and well-being in MC female outpatients, with or without coexisting IBS-like symptoms, and to examine the prevalence of GnRH antibodies in these patients.

MATERIAL AND METHODS

Women with biopsy-verified MC, at any outpatient clinic of the Departments of Gastroenterology, Skåne, between 2002 and 2010 were invited to participate in the study. The questionnaires Gastrointestinal Symptom Rating Scale (GSRS), Psychological General Well-being Index (PGWB), Visual Analogue Scale for Irritable Bowel Syndrome (VAS-IBS), and Rome III were answered and blood samples collected. Autoantibodies (IgG, IgA, and IgM) against GnRH and GnRH-R (extracellular peptide of receptor) were determined by an enzyme-linked immunosorbent assay.

RESULTS

Altogether, 158 (66%) of 240 invited patients with MC were recruited to the study. Of these, 133 (55%) patients also accepted to provide blood samples. Patients with IBS-like symptoms (55%) experienced more symptoms and worse psychological well-being in all dimensions in GSRS and PGWB, and in all symptoms but constipation in VAS-IBS compared to patients without IBS symptoms. Only a minority of patients expressed antibodies against GnRH or GnRH-R, which did not differ between groups.

CONCLUSIONS

MC patients fulfilling criteria for IBS experience more gastrointestinal symptoms and worse psychological well-being than those who do not. Autoantibodies against GnRH or GnRH-R are not frequently observed in MC patients.

[Etiology of chronic diarrhea in the elderly in Hospital Edgardo Rebagliati, Lima-Peru]

INTRODUCTION

The impact of chronic diarrhea in the elderly is disproportionate by several factors causing increased morbidity and mortality.

OBJECTIVE

To describe the main features about the chronic diarrhea in elderly patients from Edgardo Rebagliati Hospital (Lima-Peru) during the period January 2005 to December 2011,

METHOD

A descriptive and retrospective study in which we reviewed the medical records of elderly patients with the diagnosis of chronic diarrhea, pouring in a data collection sheet.

RESULTS

We reviewed the medical records of 202 patients. The mean age was 73.5 ± 6.7 years, with most women (57.43%). Major comorbidities were cardiovascular (60.4%) and endocrine (27.2%). The half time of illness was 21.6 ± 13.6 weeks. The most requested tests were CBC, biochemistry, albumin, coprofuncional, parasitological and colonoscopy. The most common type of diarrhea was the organic (84.16%). Among the main causes were found microscopic colitis (35.15%), parasites (15.84%), irritable bowel syndrome (14.85%) and bacterial overgrowth (8.42%).

CONCLUSIONS

The most common causes of chronic diarrhea in the elderly are microscopic colitis, parasites, irritable bowel syndrome and bacterial overgrowth.

Non-IBD colitides (eosinophilic, microscopic)

Microscopic colitis includes the terms lymphocytic colitis and collagenous colitis, and is a common cause of chronic diarrhoea in older adults. The incidence of microscopic colitis has increased over time and has reached levels comparable to other forms of inflammatory bowel disease. In this chapter, an updated review on the epidemiology, diagnosis and treatment of microscopic colitis has been provided. There is limited data available about eosinophilic colitis, which is the least common of the eosinophilic GI disorders. It is important to rule out the secondary causes of colonic eosinophilia in patients with suspected eosinophilic colitis.

Microscopic colitis in patients with chronic diarrhea and normal colonoscopic findings in Southern China

BACKGROUND AND OBJECTIVES

Microscopic colitis includes lymphocytic colitis and collagenous colitis. The entity is considered as an important cause for unknown chronic diarrhea, but rarely reported in China before. This study aimed to determine the prevalence of microscopic colitis in patients with chronic diarrhea and normal colonoscopy findings in Southern China, and to reveal the clinical feature of microscopic colitis in these patients.

METHODS

Patients with chronic diarrhea and normal colonoscopic findings were enrolled from three hospitals in Southern China from January, 2009 to June, 2010. Multiple colorectal biopsies were obtained in these patients and histological examination was underwent with hematoxyin and eosin stain, Masson's trichrome stain and immunohistochemistry for tenascin to screen lymphocytic colitis and collagenous colitis. The clinical symptom and risk factor of microscopic colitis were assessed by comparing with controls. The diagnostic overlap between microscopic colitis and irritable bowel syndrome or functional diarrhea was also analyzed.

RESULTS

Randomly mucosal biopsies were performed in 613 patients with chronic diarrhea and normal or near normal colonoscopic finding. Fifty-nine cases of lymphocytic colitis and 28 cases of collagenous colitis were found by histological examination. The rates of rheumatoid arthritis in lymphocytic colitis group (15.4 %) and collagenous colitis group (14.3 %) were significant higher than in control group (2.2 %). Rheumatoid arthritis was confirmed as the risk factor of microscopic colitis by logistic regression analysis. There was no difference on the symptoms among the controls, patients with lymphocytic colitis, and patients with collagenous colitis. There were 13.8 % (12/87) of patients with microscopic colitis fulfilled Rome III criteria of irritable bowel syndrome and 42.5 % (37/87) fulfilled the criteria of functional diarrhea.

CONCLUSIONS

Microscopic colitis is not an uncommon disorder in Chinese population. Rheumatoid arthritis is the risk factor of microscopic colitis. Microscopic colitis has a symptomatic overlap with irritable bowel syndrome and functional diarrhea. It is reasonable to obtain multiple biopsies in patients with chronic diarrhea when the mucosa grossly normal at colonoscopy.

[Prevalence of microscopic colitis in a group of patients from Montevideo, Uruguay]

INTRODUCTION

The microscopic colitis (MC) is characterized by the presence of aqueous chronic diarrhea (ACD) with inflammatory elements in the colon only detectable by microscopy.

OBJECTIVES

To know the prevalence of MC in the group of patients with ACD attending the Endoscopy Service of the British Hospital from Montevideo.

MATERIAL AND METHODS

We retrospectively included patients with ACD who were studied by endoscopy during a period of 5 years and the endoscopy was normal or showed minimal alterations. Biopsies in different parts of the colon were taken to this group of patients aiming to diagnose this entity.

RESULTS

We included 180 patients, 101 women (56%) and 79 men (44%). No lesion was found in the endoscopy in 67% of them, 27% had a diverticular colopathy and 5% a non-specific colitis. Out of the total number of patients, 9% had a histological study compatible with MC, 82% had lymphocytic colitis (CL) and 18% collagenous colitis (CC), with a ratio between men and women of 1.8:1 and 1:2, respectively. The mean age for the diagnosis was 43 years old in the group of CL and 61 years old in the group of CC. Endoscopic lesions were not found in 94% of patients with MC and only 1 patient presented a non-specific colitis at the endoscopy. The 65% of the remaining patients did not show histological alterations and 26% of them presented non-specific inflammatory changes.

CONCLUSIONS

The prevalence of MC in our series was similar to that found in other publications and alterations in the colonic mucosa were not found in most cases. The CL was the most frequent form of presentation and was found at an earlier age than the CC. The CL was more frequent in men. Knowing that the CM is a rare illness in our environment, these findings suggest the importance of taking multiple biopsies from different parts of the colon when patients with ACD are studied.

Microscopic colitis -- a common cause of diarrhoea in older adults

Diarrhoeal diseases are common in older populations and often markedly affect their quality of life. Although there are numerous potential causes, microscopic colitis (MC) is increasingly recognised as a major diagnostic entity in older individuals. MC is comprised of two distinct histological forms - collagenous colitis and lymphocytic colitis, both of which frequently occur in older populations. Recent studies suggest that between 10 and 30% of older patients investigated for chronic diarrhoea with an endoscopically normal appearing colon will have MC. It is unclear why MC is more common in older populations, but it is associated with both autoimmune disorders and several drugs that are commonly used by seniors. A definitive diagnosis can only be made with colonic biopsies. Since MC was first described in 1976 and only recently recognised as a common cause of diarrhoea, many practising physicians may not be aware of this entity. In this review, we outline the epidemiology, risk factors associated with MC, its pathophysiology, the approach to diagnosis and the management of these individuals.

Mucosal immune activation in irritable bowel syndrome: gender-dependence and association with digestive symptoms

OBJECTIVES

Immune activation may be involved in the pathogenesis of irritable bowel syndrome (IBS). However, the relative magnitude of this immune component and its correlation with gender and gastrointestinal complaints in IBS patients remains poorly elucidated.

METHODS

We enrolled 48 IBS patients, with either diarrhea or constipation, 12 patients with microscopic colitis, 20 patients with ulcerative colitis, and 24 healthy controls. Colonic immunocytes were identified with quantitative immunohistochemistry on mucosal biopsies. Gastrointestinal symptoms were assessed using a validated questionnaire.

RESULTS

IBS patients showed a significant 72% increase in mucosal immune cells compared to controls (P<0.001). Further analyses showed that increased immune cells were present in 50% of the IBS patients. The magnitude of the immune infiltrate in IBS was significantly lower than that of microscopic colitis or ulcerative colitis (42% and 124% increases vs. IBS, respectively; P<0.001). Compared with controls, IBS patients had increased numbers of CD3+, CD4+, and CD8+ T cells and mast cells (P<0.001). Compared to male IBS patients, female IBS patients had greater numbers of mast cells (P=0.066), but lower numbers of CD3+ and CD8+ T cells (P=0.002 and <0.001, respectively). Mucosal mast cell infiltration of IBS patients was significantly associated with abdominal bloating frequency (P=0.022) and with symptoms of dysmotility-like dyspepsia (P=0.001), but not ulcer-like dyspepsia.

CONCLUSIONS

A large subset of IBS patients shows gender-dependent mucosal infiltration of immunocytes that correlates with abdominal bloating and dysmotility-like dyspepsia. These results provide the rationale for considering immune mechanisms as a pathophysiological component in a subset of IBS patients.

[Microscopic colitis - review]

Microscopic colitis (MC) is an encompassing term for two diseases; collagenous colitis and lymphocytic colitis. The colon appears normal by colonoscopy and a diagnosis is only obtained with a biopsy. The histopathology of collagenous colitis is mainly characterized by a thickening of the subepithelial basement membrane of the colonic mucosa with a band of collagen. Lymphocytic colitis is mainly characterized by an intraepithelial lymphocytosis without the collagen thickening. Even though the two diseases have a distinctive pathology their clinical symptoms are characterized by chronic watery diarrhea without bleeding. Microscopic colitis is thought to cause about 4-13% of all chronic diarrhea but their relative frequency is much higher among older people. The mean annual incidence for collagenous and lymphocytic colitis has been increasing. Steroids are the most effective treatment for microscopic colitis and budesonide is the most studied and effective therapy for MC. The aim of this paper is to give a review of two relatively new diseases which are among the most common cause of chronic diarrhea, especially among older people.

Microscopic colitis: a common and an easily overlooked cause of chronic diarrhoea

Microscopic colitis, comprising collagenous colitis and lymphocytic colitis, is characterised clinically by chronic watery diarrhoea, a macroscopically normal colonic mucosa where diagnostic histopathological features are seen on microscopic examination. The annual incidence of each disorder is 4-6/100,000 inhabitants, with a peak incidence in 60-70 year old individuals and a noticeable female predominance in collagenous colitis. The aetiology is unknown. Abdominal pain, weight loss, fatigue, and faecal incontinence are common symptoms in addition to chronic diarrhoea that impair the health-related quality of life of the patient. There is an association to other autoimmune disorders such as celiac disease, diabetes mellitus, thyroid disorders and arthritis. Budesonide is the best-documented short-term treatment, but the optimal long-term strategy needs further study. The long-term prognosis is good and the risk of complications including colonic cancer is low.

Spectrum of microscopic colitis in a tertiary care centre in India

INTRODUCTION

The incidence of microscopic colitis has recently increased. Although collagenous colitis and lymphocytic colitis are the two main subtypes of microscopic colitis, many patients may not fit into either category and are thus included under the header nonspecific colitis. Of late, the spectrum of microscopic colitis has widened to include minimal change colitis, microscopic colitis not otherwise specified and microscopic colitis with giant cells. There is a lack of information concerning the spectrum of microscopic colitis in Asia.

METHOD

In a retrospective analysis, case records of 29 patients diagnosed with microscopic colitis between 1999-2005 were analysed. Drug use parasitic infection and common bacterial infections were excluded. Colonoscopic/ sigmoidoscopic examination was done and multiple colonic mucosal biopsies were stained serially with haematoxylin and eosin for detailed histological examination and Masson trichrome for sub-epithelial collagen band. Based on histological criteria, patients were categorised into five subtypes: collagenous colitis (presence of collagenous thickening of surface epithelium basement membrane > 10 microm), lymphocytic colitis (intra-epithelial lymphocytes more than 20 per 100 colonocytes), minimal change colitis (crypt architectural abnormality in the form of cryptitis and crypt dilatation in the absence of increase in intraepithelial lymphocytes and subepithelial collagenous band), microscopic colitis not otherwise specified (increased inflammatory cell infiltrates in the lamina propria in the absence of other abnormalities) and microscopic colitis with giant cells.

RESULTS

Mean age of patients was 38.59 years (range 12-62). Of 29 patients with microscopic colitis, 7 (24.1%), 4 (13.8%), 7 (24.1%) and 11 (37.9%) were classified as collagenous colitis, lymphocytic colitis, minimal change colitis and microscopic colitis not otherwise specified, respectively. None of these patients had giant cells. There was no significant correlation between disease type and clinical manifestations.

CONCLUSION

Microscopic colitis has a wide histological spectrum. Cases reported as non-specific colitis, may be categorised into definite subtypes of microscopic colitis.

Etiologies and predictors of diagnosis in nonresponsive celiac disease

BACKGROUND & AIMS

Nonresponsive celiac disease (NRCD) is a common problem affecting from 7% to 30% of celiac patients. Because NRCD comprises varied and potentially morbid entities, efficient and cost-effective patient care requires knowledge of the specific causes of this disorder. The aim of this study was to determine the common etiologies of NRCD in a tertiary referral center.

METHODS

All cases of biopsy examination-proven celiac disease (CD) seen at our institution over the preceding 5 years were included in this study. NRCD was defined as a failure to respond to at least 6 months of treatment with a gluten-free diet or the re-emergence of symptoms or laboratory abnormalities typical of CD while still on treatment with a gluten-free diet.

RESULTS

A total of 113 patients with NRCD meeting the earlier-described criteria were seen from a total of 603 patients with CD (19%), however, among patients for whom we provided primary specialist care the incidence of NRCD was 10% (P < .001). Gluten exposure was the most common cause of NRCD (36%), followed by irritable bowel syndrome (22%), refractory CD (10%), lactose intolerance (8%), and microscopic colitis (6%). The mean immunoglobulin A tissue transglutaminase level in the gluten-exposed group was 67 vs 17 U/mL (normal, <20) for other diagnoses (P < .05). Weight loss and male sex were highly predictive of refractory CD (P < .05 and < .001, respectively).

CONCLUSIONS

NRCD is a common phenomenon affecting 10%-19% of celiac patients. A limited number of etiologies account for the majority of cases. Clinical factors may be used to guide evaluation.

Microscopic colitis with granuloma which responded to steroid therapy

We present a patient with chronic watery diarrhea and weight loss, in whom colonoscopic findings were consistent with microscopic colitis, but histopathological examination revealed granulomatous inflammation. A 67-year-old Japanese female with a several year history of chronic watery diarrhea and body weight loss was admitted to our hospital. Her laboratory data showed hypoalbuminemia and high levels of serum immunoglobulin G and C-reactive protein. Colonoscopic findings were grossly normal. Histopathology showed inflammatory cell infiltrates with non-necrotizing granulomas and multinucleated giant cells, indicating that this was not conventional microscopic colitis, lymphocytic colitis or collagenous colitis. After treatment with prednisolone her symptoms and laboratory data improved dramatically, and she went into remission without the necessity of further steroid treatment.

Mechanism of diarrhea in microscopic colitis

AIM: To search the pathophysiological mechanism of diarrhea based on daily stool weights, fecal electrolytes, osmotic gap and pH.

METHODS: Seventy-six patients were included: 51 with microscopic colitis (MC) [40 with lymphocytic colitis (LC); 11 with collagenous colitis (CC)]; 7 with MC without diarrhea and 18 as a control group (CG). They collected stool for 3 d. Sodium and potassium concentration were determined by flame photometry and chloride concentration by titration method of Schales. Fecal osmotic gap was calculated from the difference of osmolarity of fecal fluid and double sum of sodium and potassium concentration.

RESULTS: Fecal fluid sodium concentration was significantly increased in LC 58.11±5.38 mmol/L (P<0.01) and CC 54.14±8.42 mmol/L (P<0.05) than in CG 34.28±2.98 mmol/L. Potassium concentration in LC 74.65±5.29 mmol/L (P<0.01) and CC 75.53±8.78 mmol/L (P<0.05) was significantly less compared to CG 92.67±2.99 mmol/L. Chloride concentration in CC 36.07±7.29 mmol/L was significantly higher than in CG 24.11±2.05 mmol/L (P<0.05). Forty-four (86.7%) patients had a secretory diarrhea compared to fecal osmotic gap. Seven (13.3%) patients had osmotic diarrhea.

CONCLUSION: Diarrhea in MC mostly belongs to the secretory type. The major pathophysiological mechanism in LC could be explained by a decrease of active sodium absorption. In CC, decreased Cl/HCO₃ exchange rate and increased chloride secretion are coexistent pathways.

[Microscopic colitis--more common cause of diarrhea than believed. Biopsies are the only way to diagnosis, drug treatment is effective]

Microscopic colitis, encompassing collagenous and lymphocytic colitis, is a fairly common cause of chronic watery diarrhoea, especially in elderly women. In recent epidemiological studies the annual incidence of each disorder was 4-6/100.000 inhabitants. The aetiology is unknown. The main clinical symptoms are watery diarrhoea, weight loss and abdominal pain. Laboratory analyses are nondiagnostic, and the diagnoses rely on histopathological examination of colonic mucosal biopsies. There is an association to autoimmune diseases such as thyroid disorders, diabetes mellitus, celiac disease and arthritis. Budesonide is the best-documented treatment of collagenous colitis. It is superior to placebo in short-term therapy, but the long-term efficacy is not well studied. The evidence for other therapeutic alternatives such as loperamide, cholestyramine, bismuth subsalicylate, or 5-aminosalicylates is weak. In unresponsive severe disease azathioprine or methotrexate may be tried. There are at present no controlled data on the treatment of lymphocytic colitis. The long-term prognosis of microscopic colitis is good, serious complications are rare and there is no increased mortality.

Atypical forms of microscopic colitis: morphological features and review of the literature

Microscopic colitis is defined as a syndrome of chronic watery diarrhea with a chronic inflammatory cell infiltrate in the colonic mucosa but without significant abnormalities at colonoscopy. It encompasses at least two histopathologic entities (ie, collagenous and lymphocytic colitis). The recognition and characterization of microscopic colitis has markedly changed the approach to the evaluation and management of chronic diarrhea. The histologic features of collagenous and lymphocytic colitis are well known to most pathologists. By considering the clinical history and symptoms, the pathologist should be able to reach the correct diagnosis in most cases. However, the spectrum of morphologic changes associated with watery diarrhea syndrome appears to be broader than originally thought. Morphologic changes more often associated with chronic inflammatory bowel disease or even chronic ischemic or infectious colitis have been noted in patients with clinically established microscopic colitis. The data presented in this article suggest that microscopic colitis is a heterogeneous entity, which includes both classic and "atypical" forms. Problems arise when cases do not fit the usual pattern or lack some of the findings that are expected. Pathologists should be aware of the presence of atypical forms of microscopic colitis.

[Prevalence of the microscopic colitis to the course of the chronic diarrhea: about 150 cases]

The goal of our survey is to value the microscopic colitis frequency at 150 patients, colliged on a period of 6 years (1997-2003), that have a chronic diarrhea with a normal total coloscopy and that benefitted of systematic biopsies. The microscopic colitis has been recovered at 44 patients on 150 either 29.3%. 16 of our patients (37%) are put on Salazopyrine, they answered well to the treatment with a receding of 3 years. The microscopic colitis is a pathology whose frequency seems under valued, it is certainly benign but can give a frequent diarrhea requiring a curative treatment.