BACKGROUND: The clinical presentation of microscopic colitis (MC) consists of chronic non-bloody watery diarrhea for weeks or months at a time, abdominal pain, and changes in bowel habits with a normal mucosal appearance upon performing colonoscopy. MC includes two relatively well established histopathologic entities: collagenous colitis (CC) and lymphocytic colitis (LC) as well as atypical forms. The recognition of the microscopic findings of this heterogeneous entity is very important for making the correct diagnosis and providing proper treatment. METHODS: We studied the colonoscopic biopsy specimens that were obtained from 26 patients who had clinical findings that were suggestive of MC. RESULTS: Fifteen patients (M:F=9:6) and 9 patients (M:F=5:4) showed the microscopic features of LC and MC, not otherwise specified, respectively. CONCLUSIONS: The clinicopathologic findings (the incidence of the subtypes, the patients' ages and the male/female ratio) of the 24 cases of MC in this study showed differences from the previously reported findings from other countries. Further studies with a sufficient number of patients from multi-centers would be necessary to confirm the regional or ethnic influence.
Abdominal Pain ; Biopsy ; Colitis, Collagenous ; Colitis, Lymphocytic ; Colitis, Microscopic ; Colonoscopy ; Diarrhea ; Humans ; Incidence ; Lymphocyte Count

Microscopic colitis (MC) is a chronic idiopathic inflammatory bowel disease presenting with chronic watery diarrhea. Epidemiologic studies from Western countries have demonstrated that it is almost as common as other classic inflammatory bowel diseases, such as Crohn's disease and ulcerative colitis. Histological examination can confirm the diagnosis and differentiate between the two main subtypes of MC: collagenous colitis and lymphocytic colitis. The pathophysiology of MC remains unknown; however, possible etiologies include genetic predispositions, autoimmunity, inflammatory responses to luminal factors such as certain drugs or bacteria, and myofibroblast dysregulations. The aim of MC therapy should take into account the severity of symptoms, impact on quality of life, and evidence from clinical trials of available medical treatments.
Autoimmunity ; Bacteria ; Colitis, Collagenous ; Colitis, Lymphocytic ; Colitis, Microscopic* ; Colitis, Ulcerative ; Crohn Disease ; Diagnosis ; Diarrhea ; Epidemiologic Studies ; Genetic Predisposition to Disease ; Inflammatory Bowel Diseases ; Myofibroblasts ; Phenobarbital ; Quality of Life

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 ; Colitis, Collagenous ; Colitis, Lymphocytic ; Colitis, Microscopic* ; Diagnosis* ; Diarrhea ; Health Care Costs ; Humans ; Incidence ; Inflammatory Bowel Diseases ; Natural History ; Prevalence* ; Prospective Studies ; Quality of Life ; Recurrence ; Risk Factors

Staphylococcus aureus (S. aureus) is occasionally a normal inhabitant of the gastrointestinal tract, and rarely considered a cause of enterocolitis. Methicillin-resistant Staphylococcal enterocolitis may cause persistent diarrhea leading to severe complications and even death, without appropriate treatment. Lymphocytic colitis (LC), a subtype of microscopic colitis, is a relatively common cause of chronic watery diarrhea. We report the case of a 73-year-old woman with profuse watery diarrhea caused by methicillin-resistant S. aureus. Soon after treatment of her enterocolitis with vancomycin the patient's general condition and symptoms improved, although the diarrhea persisted. Through colonoscopic biopsy and immunohistochemical staining, overt LC was diagnosed, and prompt therapy with budesonide was initiated.
Aged ; Biopsy ; Budesonide ; Colitis, Lymphocytic ; Colitis, Microscopic ; Diarrhea ; Enterocolitis ; Female ; Gastrointestinal Tract ; Humans ; Methicillin Resistance ; Staphylococcus aureus ; Vancomycin

BACKGROUND/AIMS: Microscopic colitis (MC) encompasses collagenous and lymphocytic colitis and is characterized by chronic diarrhea. In cases of MC, colonic mucosae are macroscopically normal, and diagnostic histopathological features are observed only upon microscopic examination. We designed a prospective multicenter study to determine the clinical features, pathological distribution in the colon and prevalence of MC in Korea. METHODS: We prospectively enrolled patients having watery diarrhea no more than 3 times a day between March 2008 and February 2009. We obtained patient histories and performed colonoscopies with random biopsies at each colon segment. RESULTS: A total of 100 patients with chronic diarrhea were enrolled for a normal colonoscopy and stool exam. MC was observed in 22 patients (22%) (M:F 1.2:1; mean age, 47.5 years). Of those 22 patients, 18 had lymphocytic colitis and 4 had collagenous colitis. The entire colon was affected in only 3 cases (13.6%), the ascending colon in 6 cases (27.2%), the transverse colon in 3 cases (13.6%), and the left colon in 3 cases (13.6%). More than 2 segments were affected in 7 cases (31.8%). Nonsteroidal anti-inflammatory drug-associated MCs were observed in 4 cases (18.2%), 3 of which showed improved diarrhea symptoms following discontinuation of the medication. Frequently associated symptoms were abdominal pain and weight loss. Autoimmune diseases were observed in 4 cases (18.2%). Half of the 22 patients with MC improved with conservative care by loperamide or probiotics. CONCLUSIONS: In a prospective multicenter study of Korean patients with chronic diarrhea, the frequency of MC was found to be approximately 20%, similar to the percentage observed in Western countries. Therefore, the identification of MC is important for the adequate management of Korean patients with chronic diarrhea.
Abdominal Pain ; Autoimmune Diseases ; Biopsy ; Colitis, Collagenous ; Colitis, Lymphocytic ; Colitis, Microscopic ; Collagen ; Colon ; Colon, Ascending ; Colon, Transverse ; Colonoscopy ; Diarrhea ; Humans ; Loperamide ; Mucous Membrane ; Prevalence ; Prospective Studies ; Weight Loss

BACKGROUND/AIMS: Collagenous colitis (CC) and lymphocytic colitis (LC) are characterized by chronic diarrhea and normal radiologic and endoscopic findings. These are currently not uncommon entities whose incidence in increasing as more clinicians take biopsies from macroscopically normal colons. The purpose of this study was to examine the clinical features and characteristics in microscopic colitis. METHODS: From January 2003 to December 2006, medical records were reviewed from 80 patients with chronic diarrhea, who had normal colonoscopic findings but underwent biopsy. Patients with microscopic colitis were identified by reviewing the pathology databases and by reviewing biopsies. RESULTS: Microscopic colitis was diagnosed in 12 patients (15%). Six patients with CC (Male:Female=2:4, mean age 54+/-20.1 years) and 6 patients with LC (Male:Female=5:1, mean age 51.2+/-21.4 years) were identified. Autoimmune disease was diagnosed in 4 patients (33%). Drug-induced disease was suspected in 3 patients (25%). The inciting drugs were NSAIDs, ticlopidine, ranitidine, and acarbose. Complete or partial resolution of diarrhea was achieved in all patients, including spontaneous resolution in 2 patients. Antidiarrheal drugs, mesalazine, and cholestylamine were highly effective in both diseases. Recurrence of symptoms occurred in 2 patients (17%). They are taking medicine at present. CONCLUSIONS: Microscopic colitis is a relatively common cause of chronic diarrhea that appears to be increasing in incidence. We reported clinical features, characteristics, treatment, and response of microscopic colitis in our experience.
Acarbose ; Anti-Inflammatory Agents, Non-Steroidal ; Antidiarrheals ; Autoimmune Diseases ; Biopsy ; Colitis, Collagenous ; Colitis, Lymphocytic ; Colitis, Microscopic ; Colon ; Diarrhea ; Humans ; Incidence ; Medical Records ; Mesalamine ; Ranitidine ; Recurrence ; Ticlopidine

Chronic diarrhea is usually associated with a number of non-infectious causes. When definitive treatment is unavailable, symptomatic drug therapy is indicated. Pharmacologic agents for chronic diarrhea include loperamide, 5-hydroxytryptamine type 3 (5-HT3) receptor antagonists, diosmectite, cholestyramine, probiotics, antispasmodics, rifaximin, and anti-inflammatory agents. Loperamide, a synthetic opiate agonist, decreases peristaltic activity and inhibits secretion, resulting in the reduction of fluid and electrolyte loss and an increase in stool consistency. Cholestyramine is a bile acid sequestrant that is generally considered as the first-line treatment for bile acid diarrhea. 5-HT3 receptor antagonists have significant benefits in patients with irritable bowel syndrome (IBS) with diarrhea. Ramosetron improves stool consistency as well as global IBS symptoms. Probiotics may have a role in the prevention of antibiotic-associated diarrhea. However, data on the role of probiotics in the treatment of chronic diarrhea are lacking. Diosmectite, an absorbent, can be used for the treatment of chronic functional diarrhea, radiation-induced diarrhea, and chemotherapy-induced diarrhea. Antispasmodics including alverine citrate, mebeverine, otilonium bromide, and pinaverium bromide are used for relieving diarrheal symptoms and abdominal pain. Rifaximin can be effective for chronic diarrhea associated with IBS and small intestinal bacterial overgrowth. Budesonide is effective in both lymphocytic colitis and collagenous colitis. The efficacy of mesalazine in microscopic colitis is weak or remains uncertain. Considering their mechanisms of action, these agents should be prescribed properly.
Abdominal Pain ; Anti-Inflammatory Agents ; Bile ; Budesonide ; Cholestyramine Resin ; Citric Acid ; Colitis, Collagenous ; Colitis, Lymphocytic ; Colitis, Microscopic ; Diarrhea* ; Drug Therapy ; Humans ; Irritable Bowel Syndrome ; Loperamide ; Mesalamine ; Parasympatholytics ; Probiotics ; Receptors, Serotonin, 5-HT3 ; Serotonin

Microscopic polyangiitis (MPA) is a systemic small vessel vasculitis, which is frequently complicated with rapidly progressive necrotizing glomerulonephritis. Patients with MPA often have demonstrable perinuclear antineutrophil cytoplasm antibodies (p-ANCA) in serum. The most common age of onset is 40 to 60 years and is more common in men. Gastrointestinal (GI) tract involvement is present in about 30-40%. Small bowel involvement is more common and ischemic colitis in the rectum is rare. We have experienced a case of microscopic polyangiitis with ischemic colitis in the rectum, p-ANCA positive and cresent formation on renal biopsy. A 72-year-old woman was admitted with two weeks history of abdominal pain. Total colonoscopy revealed colon obstruction with severe mucosal edema. Urine study showed hematuria and proteinuria. Serum creatinine was elevated progressively. Serume p-ANCA was positive. The titer of p-ANCA was decreased and colon obstruction was recovered after steroid and cyclophosphamide therapy.
Abdominal Pain ; Age of Onset ; Aged ; Antibodies ; Antibodies, Antineutrophil Cytoplasmic ; Biopsy ; Colitis, Ischemic* ; Colon ; Colonoscopy ; Creatinine ; Cyclophosphamide ; Cytoplasm ; Edema ; Female ; Glomerulonephritis ; Hematuria ; Humans ; Male ; Microscopic Polyangiitis* ; Proteinuria ; Rectum ; Vasculitis

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.
Anti-Anxiety Agents ; Axis, Cervical Vertebra ; B-Lymphocytes ; Colitis, Microscopic ; Diet ; Enteroendocrine Cells ; Humans ; Immunity, Mucosal ; Inflammation ; Inflammatory Bowel Diseases ; Irritable Bowel Syndrome ; Life Style ; Mast Cells ; Narcotics ; T-Lymphocytes

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.
Biopsy ; Colitis, Microscopic/*metabolism ; Colon/pathology ; Cyclooxygenase 2/*metabolism ; Cytokines/metabolism ; Diarrhea/metabolism ; Humans ; Interferon-gamma/metabolism ; Interleukin-17/*metabolism ; Intestinal Mucosa/pathology ; NF-kappa B/metabolism ; Nitric Oxide Synthase Type II/*metabolism ; Tumor Necrosis Factor-alpha/metabolism