Microscopic Colitis: A Concise Review for Clinicians.

Microscopic colitis (MC) is an inflammatory disease of the colon and a common cause of chronic watery diarrhea, predominantly in older patients. Microscopic colitis encompasses 2 different subtypes, lymphocytic colitis and collagenous colitis. The colon typically appears normal endoscopically in MC, and the diagnosis requires histologic evaluation. Whereas recent studies suggest that the incidence of MC has plateaued, given the aging of the population, the prevalence of MC will likely increase. Risk factors for MC include increasing age; female sex; presence of other autoimmune diseases; and possibly use of certain medications, including proton pump inhibitors, nonsteroidal anti-inflammatory drugs, selective serotonin reuptake inhibitors, and statins. The clinical presentation of MC is nonspecific and includes watery nonbloody diarrhea, nocturnal stools, fecal urgency, abdominal pain, arthralgias, and weight loss. The disease course of MC is variable; some patients experience occasional, intermittent symptoms, and others demonstrate more chronic and even progressive symptoms. The approach to treatment is similar for both lymphocytic colitis and collagenous colitis and should be guided by the severity of the patient's symptoms. Offending medications highly associated with MC should be eliminated as clinically possible. In patients with mild symptoms, antidiarrheals such as loperamide are the initial choice; for moderate-severe disease, budesonide is recommended for induction of clinical remission. In those with recurrent symptoms, low-dose budesonide may be required for maintenance therapy with close monitoring for potential adverse effects. In rare cases, immunomodulators may be required.

Incidence and Prevalence of Microscopic Colitis Between 2001 and 2016: A Danish Nationwide Cohort Study.

BACKGROUND AND AIMS: Epidemiological studies suggest an increasing global incidence of microscopic colitis, including collagenous colitis and lymphocytic colitis. We aimed to investigate the incidence and prevalence of microscopic colitis in Denmark. METHODS: In a nationwide cohort study, we included all incident patients with a recorded diagnosis of collagenous colitis or lymphocytic colitis in the Danish Pathology Register between 2001 and 2016. RESULTS: A total of 14 302 patients with microscopic colitis-8437 [59%] with collagenous and 5865 [41%] with lymphocytic colitis-were identified during the study period. The prevalence in December 2016 was estimated to be 197.9 cases per 100 000 inhabitants. Microscopic colitis was more prevalent among females (n = 10 127 [71%]), with a mean annual incidence of 28.8, compared with 12.3 per 100 000 person-years among males. The overall mean incidence during the study period was 20.7 per 100 000 person-years. Mean age at time of diagnosis was 65 years (standard deviation [SD]:14) for microscopic colitis, 67 [SD:13] for collagenous colitis, and 63 [SD:15] for lymphocytic colitis. The overall incidence increased significantly from 2.3 cases in 2001 to 24.3 cases per 100 000 person-years in 2016. However, the highest observed incidence of microscopic colitis was 32.3 cases per 100 000 person-years in 2011. Large regional differences were found, with the highest incidence observed in the least populated region. CONCLUSIONS: The incidence of microscopic colitis in Denmark has increased 10-fold during the past 15 years and has now surpassed that of Crohn's disease and ulcerative colitis. However, incidence has stabilised since 2012, suggesting that a plateau has been reached.

Microscopic Colitis: A Challenging Disorder.

BACKGROUND: The clinical importance of microscopic colitis (MC) is increasing. This is explained by both the increasing incidence and the challenges posed by the disease. However, recent MC data also reveal a number of doubts and uncertainties. SUMMARY: This review focuses on current knowledge of MC and highlights the various controversies and criticisms regarding the clinical data about definitions, subtypes, pathogenesis, diagnosis, and treatment of this condition. Key Messages: The diagnosis of MC is based on histology, which distinguishes 2 subtypes. However, transitional forms often cause misclassification, which calls into question the reality (specificity, meaning) of the distinction between the 2 forms. The location of the colon biopsy is not defined by international consensus. There is no credible, clear explanation for the incidence increase. The pathogenesis is unknown, probably multifactorial, but the importance of the immunological background is increasing. The natural history of the disease and the underlying cause of relapses are unclear. It is suggested that MC would be the prelude of IBD. Further data collection is needed to clarify these issues.

Colonic Manifestations and Complications Are Relatively Under-Reported in Systemic Sclerosis: A Systematic Review.

OBJECTIVES: Although systemic sclerosis (SSc) is known to affect the gastrointestinal (GI) tract, most of the literature focuses on esophageal, small intestinal, or anorectal manifestations. There have been no reviews focused on large bowel SSc complications in over 30 years. The aim of this study is to perform a systematic review of colonic manifestations and complications of SSc. METHODS: An experienced librarian conducted a search of databases, including English and Spanish articles. The search used keywords including "systemic sclerosis," "scleroderma," and "colon." A systematic review was performed using Preferred Reporting Items for Systematic Review and Meta-Analyses guidelines. Case reports/series were screened for validity by adapting from criteria published elsewhere. RESULTS: Of 1,890 articles, 74 met selection criteria. Fifty-nine of the 77 articles were case reports/series. The most common article topics on colonic SSc complications were constipation/dysmotility (15), colonic volvulus (8), inflammatory bowel disease (7), microscopic colitis (6), megacolon (6), and telangiectasia (6). Colonic manifestations constituted 24% of articles on GI complications of SSc. There were a total of 85 cases (84% women, with a median age of onset of colon complication of 52 years). Limited cutaneous SSc phenotype (65.6%) was more common than diffuse (26.2%). Patients frequently had poor outcomes with high mortality related to colonic complications (27%). Recent studies explore contemporary topics such as the microbiome in SSc and prucalopride for chronic constipation in SSc. DISCUSSION: Colonic complications comprise a large proportion of the published reports on GI symptoms afflicting patients with SSc and require raised diagnostic suspicion and deliberate action to avoid potentially serious complications including death.

Microscopic colitis: pathophysiology and clinical management.

Microscopic colitis is a chronic inflammatory disease of the colon that frequently causes chronic watery diarrhoea that might be accompanied by abdominal pain, nocturnal diarrhoea, urgency, and faecal incontinence. These symptoms lead to poor quality of life and increased health-care costs. Diagnosis relies on histological examination of multiple biopsy samples from the colonic mucosa, which often show no or only few abnormalities on endoscopy. Two major histological subtypes can be distinguished-collagenous colitis and lymphocytic colitis-but incomplete and variant forms with fewer characteristic features have been reported. Here we summarise the latest evidence on epidemiology, pathogenesis, and risk factors, and discuss established and novel therapeutic options for clinical remission. Finally, we propose an updated treatment algorithm. Further prospective studies are needed to clarify the natural history of microscopic colitis, supported by validated criteria for the assessment of disease activity.

Emerging Topics in Gastroenterology.

The bacteria and fungi in the human gut make up a community of microorganisms that lives in symbiosis with humans, engaging in numerous diverse interactions that influence health. This article outlines the current knowledge on emerging topics in gastroenterology, including microbiome and probiotics, fecal microbiota transplantation, cyclic vomiting syndrome, eosinophilic esophagitis, and microscopic colitis.

Is Epstein-Barr virus infection associated with the pathogenesis of microscopic colitis?

BACKGROUND: Epstein-Barr virus (EBV) has been associated with inflammation in the colon, particularly in patients with inflammatory bowel disease (IBD). Even if a relevant plasmocytosis, similar to IBD, is present in microscopic colitis (MC), the frequency of EBV infection in this setting is unknown. OBJECTIVES: We aimed to compare the frequency of colonic EBV infection in patients with MC, ulcerative colitis (UC), and irritable bowel syndrome (IBS). STUDY DESIGN: The frequency of colonic EBV infection in biopsies of 30 patients with MC, 30 patients with UC, and 30 controls with IBS was retrospectively assessed. PCR was performed to detect viral EBV DNA in colonic biopsies. In situ hybridization was also performed to identify and localize EBV-encoded small RNA1 and 2 (EBERs) within cells. RESULTS: The presence of EBV DNA was detected in 27 out of 30 MC patients, in 20 out of 30 UC cases, and in none of IBS group. The frequency of EBV DNA in MC was significantly higher compared with that reported in UC (90.0% vs. 66.7%, p=0.03). EBERs+ cells were observed in 18 out of 30 MC patients, in only 3 out of 30 UC patients (60.0% vs. 10.0%, p<0.001), and in none of IBS group. CONCLUSIONS: EBV infection is almost always detectable in the colonic mucosa of patients with MC. Further studies are necessary to confirm this association and to clarify the role of EBV in MC and, more generally, in colonic inflammation.

Oligoclonal T-cell Receptor Repertoire in Colonic Biopsies of Patients with Microscopic Colitis and Ulcerative Colitis.

BACKGROUND: Microscopic colitis (MC), comprising collagenous colitis (CC) and lymphocytic colitis (LC), is a type of variation of inflammatory bowel diseases. Local T-cell infiltration in the mucosa plays a major role in MC immunopathology. METHODS: To understand diversity and clonality of infiltrating T cells, we analyzed the T-cell receptor beta (TCRß) chains in colonic biopsies of MC, ulcerative colitis (UC), and their remission counterparts (CC/LC-HR [histological remission] or UC-R [remission]) compared with patients with noninflamed colons using next-generation sequencing. RESULTS: Compared with controls and patients with CC, patients with LC had significantly lower diversity with significantly lower evenness and richness in TCRVß-Jß gene segments. Similarly, patients with LC-HR had lower diversity because of significantly lower TCRVß-Jß clone richness. Patients with UC and UC-R showed significantly higher diversity and richness. Univariate and multivariate analyses were performed to identify TCRVß-Jß gene segments differentiating disease types from controls or their remission counterparts. Patients with LC were discriminated from controls by 12 clones and from patients with CC by 8 clones. Neither univariate nor multivariate analyses showed significance for patients with CC or CC-HR compared with controls. Patients with UC and UC-R had 16 and 14 discriminating clones, respectively, compared with controls. CONCLUSIONS: Altogether, patients with MC and UC showed an oligoclonal TCRß distribution. TCRVß-Jß clone types and their diversity were distinctive between patients with CC and LC, as well as for patients with UC, suggesting different pathophysiological mechanisms according to disease type and stage. This study suggests that CC and LC are different entities because of differences in immunoregulatory responses, as mirrored by their T-cell repertoire.

Microscopic colitis: A literature review.

Microscopic colitis (MC) refers to chronic inflammation of the colon which is characterized by histologic changes at the level of a radiologically and endoscopically normal mucosa. It is a common cause of chronic non-bloody diarrhea that occurs primarily in older individuals; however, there are few studies in the literature with strong scientific evidence compared to other inflammatory bowel diseases (IBD), which limits the knowledge of physicians and pathologists. This article aims to review the information on MC, describing diagnostic methods and drugs available for treatment. We conducted a search of the Pubmed database and CAPES Portal using the keywords "microscopic colitis", "collagenous colitis", "lymphocytic colitis", and "review" for selection of articles published between 1996 and 2015 related to the topic. Based on the studies discussed in this review, we conclude that MC is a relatively new gastrointestinal disorder, most studies are incipient particularly with respect to pathophysiology and immunology, and budesonide is the best documented short-term treatment. However, further studies are needed to elucidate the best strategy for treatment in the long term.

Microscopic colitis: A literature review / Colite microscópica: uma revisão da literatura

SUMMARY Microscopic colitis (MC) refers to chronic inflammation of the colon which is characterized by histologic changes at the level of a radiologically and endoscopically normal mucosa. It is a common cause of chronic non-bloody diarrhea that occurs primarily in older individuals; however, there are few studies in the literature with strong scientific evidence compared to other inflammatory bowel diseases (IBD), which limits the knowledge of physicians and pathologists. This article aims to review the information on MC, describing diagnostic methods and drugs available for treatment. We conducted a search of the Pubmed database and CAPES Portal using the keywords “microscopic colitis”, “collagenous colitis”, “lymphocytic colitis”, and “review” for selection of articles published between 1996 and 2015 related to the topic. Based on the studies discussed in this review, we conclude that MC is a relatively new gastrointestinal disorder, most studies are incipient particularly with respect to pathophysiology and immunology, and budesonide is the best documented short-term treatment. However, further studies are needed to elucidate the best strategy for treatment in the long term.

RESUMO Colite microscópica (CM) corresponde à inflamação crônica do cólon que se manifesta por modificações histológicas em nível de uma mucosa radiológica e endoscopicamente normal. É uma causa comum de diarreia crônica não sanguinolenta que ocorre principalmente em indivíduos idosos; porém, há poucos trabalhos na literatura com forte evidência científica quando comparada à de outras doenças inflamatórias intestinais (DII), o que limita seu conhecimento por médicos e patologistas. Este artigo tem como objetivo revisar as informações referentes à CM descrevendo os meios diagnósticos e os medicamentos disponíveis para o tratamento. Foi realizada uma pesquisa na base de dados Pubmed e no Portal da CAPES entre 1996 e 2015 utilizando as palavras-chave “colite microscópica”, “colite colagenosa”, “colite linfocítica” e “revisão” para seleção de artigos relacionados ao tema. Diante dos trabalhos analisados, conclui-se que a CM é uma desordem gastrointestinal relativamente nova, a maioria dos estudos são incipientes, principalmente quanto à imunologia e fisiopatologia, e a budesonida é o tratamento em curto prazo mais bem documentado. Todavia são necessários novos estudos para elucidar qual é a melhor estratégia em longo prazo.

Current concepts on microscopic colitis: evidence-based statements and recommendations of the Spanish Microscopic Colitis Group.

BACKGROUND: Microscopic colitis (MC) is an underdiagnosed inflammatory bowel disease. AIM: To develop an evidence-based clinical practice guide on MC current concepts. METHODS: Literature search was done on the Cochrane Library, EMBASE and MEDLINE electronic databases, which were consulted covering the period up until March 2015. Work groups were selected for each of the reviewed topics, with the purpose of drafting the initial statements and recommendations. They subsequently underwent a voting process based on the Delphi method. Each statement/recommendation was accompanied by the result of the vote the level of evidence, and discussion of the corresponding evidence. The grade of recommendation (GR) using the GRADE approach was established for diagnosis and treatment recommendations. RESULTS: Some key statements and recommendations are: advancing age increases the risk of developing MC, mainly in females. The symptoms of MC and IBS-D may be similar. If MC is suspected, colonoscopy taking biopsies is mandatory. Treatment with oral budesonide is recommended to induce clinical remission in patients with MC. Oral mesalazine is not recommended in patients with collagenous colitis for the induction of clinical remission. The use of anti-TNF-alpha drugs (infliximab, adalimumab) is recommended for the induction of remission in severe cases of MC that fail to respond to corticosteroids or immunomodulators, as an alternative to colectomy. CONCLUSIONS: This is the first consensus paper on MC based on GRADE methodology. This initiative may help physicians involved in care of these patients in taking decisions based on evidence.

[MICROSCOPIC COLITIS: CURRENT STATE-OF-THE-ART].

The aim of the study was to analyse publications on practical aspects of the management of microscopic colitis (MC) as a common manifestation of diarrheic syndrome in aged subjects. Many etiopathogenetic issues remain debatable. Major difficulties are encountered in differential diagnostics. Of special importance is the relationship between MC, autoimmune and inflammatory intestinal diseases. Approaches to MC therapy vary from the use of antidiarrheal agents to comprehensive immunosuppressive treatment.

[MICROSCOPIC COLITIS: THE CLINICAL CASE].

During past years incidence and prevalence of microscopic colitis (MC) have increased, that is possible caused to the improvement of knowledge of doctors about the disease. This article contain modern views on epidemiology, diagnostic and variant of microscopic colitis treatment. A typical clinical picture of MC in the form of recurrent a watery diarrhea, with the absence of pathologic changes at roentgenologic and endoscopic investigations is described with the example of a clinical case.

Symptomatic overlap in patients with diarrhea predominant irritable bowel syndrome and microscopic colitis in a sub group of Bangladeshi population.

Microscopic Colitis (MC) and diarrhea predominant irritable bowel syndrome (IBS-D) has almost similar clinical feature but MC is diagnosed by histologic criteria and IBS is diagnosed by symptom-based criteria. There is ongoing debate about the importance of biopsies from endoscopically normal colonic mucosa in the investigation of patients with IBS-D. Aim of this study was to assess the prevalence of MC in patient with IBS-D and to determine the distribution of MC in the colon. This observational study was conducted in department of Gastroenterology, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh from January 2008 to December 2009. Patients were evaluated thoroughly & who meet Rome-II criteria with normal routine laboratory tests, were included in the study. Colonoscopy was done and biopsies were taken from the caecum, transverse colon, descending colon, and rectum. Out of total 60 patients, 22 had Lymphocytic Colitis (LC), 28 had nonspecific microscopic colitis (NSMC) and 10 had irritable bowel syndrome noninflamed (IBSNI). The distribution of LC was restricted to proximal colon in 15 patients, in the left colon in 2 patients and diffuses throughout the colon in 5 patients. There is considerable symptom overlap between the patients of IBS-D and patients with microscopic colitis. Without colonoscopic biopsy from multiple sites, possibility of MC cannot be excluded in patients with IBS-D and it can be said that clinical symptom based criteria for irritable bowel syndrome are not sufficient enough to rule out the diagnosis of microscopic colitis.

Celiac disease: management of persistent symptoms in patients on a gluten-free diet.

AIM: To investigate all patients referred to our center with non-responsive celiac disease (NRCD), to establish a cause for their continued symptoms. METHODS: We assessed all patients referred to our center with non-responsive celiac disease over an 18-mo period. These individuals were investigated to establish the eitiology of their continued symptoms. The patients were first seen in clinic where a thorough history and examination were performed with routine blood work including tissue transglutaminase antibody measurement. They were also referred to a specialist gastroenterology dietician to try to identift any lapses in the diet and sources of hidden gluten ingestion. A repeat small intestinal biopsy was also performed and compared to biopsies from the referring hospital where possible. Colonoscopy, lactulose hydrogen breath testing, pancreolauryl testing and computed tomography scan of the abdomen were undertaken if the symptoms persisted. Their clinical progress was followed over a minimum of 2 years. RESULTS: One hundred and twelve consecutive patients were referred with NRCD. Twelve were found not to have celiac disease (CD). Of the remaining 100 patients, 45% were not adequately adhering to a strict gluten-free diet, with 24 (53%) found to be inadvertently ingesting gluten, and 21 (47%) admitting non-compliance. Microscopic colitis was diagnosed in 12% and small bowel bacterial overgrowth in 9%. Refractory CD was diagnosed in 9%. Three of these were diagnosed with intestinal lymphoma. After 2 years, 78 patients remained well, eight had continuing symptoms, and four had died. CONCLUSION: In individuals with NRCD, a remediable cause can be found in 90%: with continued gluten ingestion as the leading cause. We propose an algorithm for investigation.

Urine sugars for in vivo gut permeability: validation and comparisons in irritable bowel syndrome-diarrhea and controls.

Mucosal barrier dysfunction contributes to gastrointestinal diseases. Our aims were to validate urine sugar excretion as an in vivo test of small bowel (SB) and colonic permeability and to compare permeability in patients with irritable bowel syndrome-diarrhea (IBS-D) to positive and negative controls. Oral lactulose (L) and mannitol (M) were administered with (99m)Tc-oral solution, (111)In-oral delayed-release capsule, or directly into the ascending colon (only in healthy controls). We compared L and M excretion in urine collections at specific times in 12 patients with IBS-D, 12 healthy controls, and 10 patients with inactive or treated ulcerative or microscopic colitis (UC/MC). Sugars were measured by high-performance liquid chromatography-tandem mass spectrometry. Primary endpoints were cumulative 0-2-h, 2-8-h, and 8-24-h urinary sugars. Radioisotopes in the colon at 2 h and 8 h were measured by scintigraphy. Kruskal-Wallis and Wilcoxon tests were used to assess the overall and pairwise associations, respectively, between group and urinary sugars. The liquid in the colon at 2 h and 8 h was as follows: health, 62 ± 9% and 89 ± 3%; IBS-D, 56 ± 11% and 90 ± 3%; and UC/MC, 35 ± 8% and 78 ± 6%, respectively. Liquid formulation was associated with higher M excretion compared with capsule formulation at 0-2 h (health P = 0.049; IBS-D P < 0.001) but not during 8-24 h. UC/MC was associated with increased urine L and M excretion compared with health (but not to IBS-D) at 8-24 h, not at 0-2 h. There were significant differences between IBS-D and health in urine M excretion at 0-2 h and 2-8 h and L excretion at 8-24 h. Urine sugars at 0-2 h and 8-24 h reflect SB and colonic permeability, respectively. IBS-D is associated with increased SB and colonic mucosal permeability.

Celiac disease and microscopic colitis: a report of 4 cases.

Celiac disease (CD) is an autoimmune disorder of the small intestine that occurs in genetically predisposed people at all ages. However, it can be associated also to other immunopathological disorders, and may be associated with abnormal histology in segments of the gut other than the small bowel including colonic inflammation. While guidelines for endoscopic investigation of the jejunum are well defined, no indication is defined for colonic investigation. We describe four cases of concurrent CD and microscopic colitis (MC) diagnosed at our department over a 10-year period and analyzed the main features and outcomes of CD in this setting. The symptoms of these patients were improved initially by a gluten-free diet before the onset of MC symptoms. Two of the patients were siblings and had an atypical form of CD. The other two patients with CD and MC also presented with fibrosing alveolitis and were anti-Saccharomyces cerevisiae antibody positive. The co-existence of immune-mediated small bowel and colonic inflammatory and pulmonary diseases are not well-known, and no systematic approach has been used to identify the lifelong patterns of these immune-based diseases. Patients can develop, or present with CD at any stage in life, which can co-exist with other gastrointestinal diseases of (auto-) immune origin. In addition, the familial co-existence and prevalence of MC in patients with a prior diagnosis of CD are unclear. Clinicians managing celiac disease should be aware of these associations and understand when to consider colon investigation.