Prevalence, Pathogenesis, Diagnosis, and Management of Microscopic Colitis

Microscopic colitis (MC), which is comprised of lymphocytic colitis and collagenous colitis, is a clinicopathological diagnosis that is commonly encountered in clinical practice during the evaluation and management of chronic diarrhea. With an incidence approaching the incidence of inflammatory bowel disease, physician awareness is necessary, as diagnostic delays result in a poor quality of life and increased health care costs. The physician faces multiple challenges in the diagnosis and management of MC, as these patients frequently relapse after successful treatment. This review article outlines the risk factors associated with MC, the clinical presentation, diagnosis and histologic findings, as well as a proposed treatment algorithm. Prospective studies are required to better understand the natural history and to develop validated histologic endpoints that may be used as end points in future clinical trials and serve to guide patient management.

Colitis linfocítica en paciente con colitis ulcerosa: caso clínico / Lymphocytic colitis in a patient with ulcerative colitis: report of one case

The relationship between Microscopic Colitis and Inflammatory Bowel Disease is unclear. However, when both are diagnosed they seem to be part of a broader spectrum of the same disease, more than just a coincidence. We report a 55 years old woman with Ulcerative Colitis limited to the rectum with complete clinical and endoscopic response to standard treatment and adequate surveillance for 13 years, who abandoned treatment and control. After eight years, she consulted for mild-to-moderate non-bloody diarrhea lasting several months. Colonoscopy and basic laboratory did not show any alterations. Nevertheless, random biopsies had a characteristically pattern compatible with Lymphocytic Colitis. After the first week of treatment with budesonide the patient was asymptomatic and still in clinical remission, with negative fecal calprotectin at 6 months’ follow-up.

Cytokine Expression of Microscopic Colitis Including Interleukin-17

BACKGROUND/AIMS: Microscopic colitis is characterized by chronic watery diarrhea with specific pathological changes that can be diagnosed by microscopic examination. We performed immunohistochemical analysis of proinflammatory cytokines to investigate the pathogenic mechanism of microscopic colitis. METHODS: This study consisted of six patients with lymphocytic colitis, six patients with collagenous colitis, and six patients with functional diarrhea but normal pathology. We performed an immunohistochemical analysis of the colonic mucosal biopsies to assess the expression of cyclo-oxygenase-2, interleukin-17, nuclear factor-kappaB, interferon-gamma, inducible nitric oxide synthase, and tumor necrosis factor-alpha. We compared the quantity score of immunohistochemical staining among the groups. RESULTS: The microscopic colitis group showed significantly higher expression of cyclo-oxygenase-2, interleukin-17, nuclear factor-kappaB, and interferon-gamma compared with the control group. Cytokine expression was similar between collagenous colitis and lymphocytic colitis. However, the expression of cyclo-oxygenase-2 was higher in collagenous colitis. CONCLUSIONS: Proinflammatory cytokines, including interleukin-17 and interferon-gamma, are highly expressed in microscopic colitis. The expression of cyclo-oxygenase-2 was higher in collagenous colitis than in lymphocytic colitis. This study is the first on interleukin-17 expression in microscopic colitis patients.

Clinical features of microscopic colitis in the elderly and short-term effect of mesalamine on microscopic colitis / 中华老年医学杂志

Objective To investigate clinical features of microscopic colitis (MC) in the elderly and short-term effect of mesalamine on MC.Methods Totally 116 elderly patients with MC in our hospital were recruited from January 2011 to December 2011.Clinical manifestations,use of MC related drugs (MCRDs),pathological classifications and short-term effect of mesalazine were collected and analyzed.Results MC patients accounted for 27.6 ％ in elderly patients with chronic diarrhea,who presented with mild to middle watery or mucous stool,and only 1.7％ of MC patients accompanied with severe stomach pain.Collagenous colitis (CC) and lymphocytic enteritis (LC) accounted for 31.9％ and 68.1％,respectively in MC patients and 50％ of them had MCRDs taking history.There was a significant difference in short-term effective rate between CC group and LC group at 4 weeks after mesalazine treatment (64.9％ vs.84.8％,x2 =5.929,P=0.015).The effective rate was significantly related with the relief of pathology in LC group (x2 =5.896,P=0.015).The relapse rate had no significant difference between CC group and LC group at 8 weeks after withdrawal of mesalazine treatment (45.8％ vs.34.3 ％,P =0.317).Conclusions MC may be one of the main reasons leading to chronic diarrhea in the elderly.Mesalazine has a better effect for the short-term treatment of MC in the elderly,but the long-term maintenance therapy still needs further study.

Intestinal spirochetosis

The intestinal spirochetosis (IS) is a histologically defined by the presence of spirochetal microorganisms connected to the apical cell membrane of the colorectal epithelium. The disease is caused by a heterogeneous group of bacteria. In humans, Brachyspira aalborgi and Brachyspira pilosicoli are prevalent. The incidence ranges from 1% in developed countries to 34% in poorer areas. It affects 62.5% of colonized areas, as well as men who have intercourse with men (MSM) and those with the human immunodeficiency virus (HIV) infected. Clinical significance of such colonization is still not clear. Most infected people are asymptomatic. At the presence of gastrointestinal symptoms, treatment with metronidazole is effective. Due to unknown reasons, MSM and HIV-positive men are more likely to be symptomatic. Treponema pallidum infection must be excluded, since this agent may cause serious and permanent complications, and because the treatment is different. (AU)

A espiroquetose intestinal está definida histologicamente como a presença de micro-organismos da família spirochetaceae ligadas ao ápice das células do epitélio cólico. A doença pode ser provocada por um grupo heterogêneo de bactérias. Em humanos, a Brachyspira aalborgi e a Brachyspira pilosicoli predominam. A incidência varia desde 1%, nos países desenvolvidos, até 34% nas áreas mais pobres, atingindo taxas de colonização de 62,5%, em homens que fazem sexo com homens (HSH) e vírus da imunodeficiência humana (HIV) positivo. O significado clínico dessa colonização ainda é incerto e a maioria dos infectados permanece assintomática. Quando há sintomas gastrointestinais, o tratamento com metronidazol é efetivo. Por razões desconhecidas, HSH positivos para o HIV, apresentam mais infestação sintomática. A infecção pelo Treponema pallidum dever ser excluída, pois os tratamentos são diferentes e as complicações por essa última são mais graves e definitivas. (AU)

Irritable Bowel Syndrome in Inflammatory Bowel Disease

Clinicians are frequently challenged to interpret gastrointestinal symptoms in patients with inflammatory disease (IBD). Irritable bowel syndrome (IBS)-like symptoms are common in patients with IBD and the underlying mechanism is likely to be active or occult inflammation of the bowel rather than co-existing IBS. Biopsychosocial construct and mucosal inflammation, stress, alteration of the hypothalamic-pituitary-adrenal axis, and autonomic dysregulation are contributing factors to IBD-IBS. In particular, low-grade inflammation and immune activation are recent topics regarding the underlying mechanism. Some authors have claimed that inflammation could be a common pathophysiologic factor, in which IBS and IBD might represent the two ends of a wide spectrum of chronic inflammatory conditions. Mast cells, enteroendocrine cells, T cells, and B cells are main effector cells in immune responses. Differentiating IBS symptoms from exacerbation of IBD is important, thus preventing the use of excessive IBD medications, with the potential side effects, or narcotics. Medical treatments with anti-diarrheals, anti-spasmodics, anti-depressants, and anxiolytics can be helpful. However, abuse can lead to medication-dependency and bring about side effects. A healthy, balanced lifestyle, including diet and exercise, should be endorsed.