Reviews in Basic and Clinical Gastroenterology and HepatologyMicroscopic Colitis
Section snippets
Epidemiology
Population-based studies have found the incidence of microscopic colitis to vary between 1 and 12 per 100,000 persons per year.6, 15, 16, 20, 21, 22 In Europe, the incidence of collagenous colitis has been reported to vary from 1.1 to 5.2 per 100,000 persons per year and the incidence of lymphocytic colitis from 3.1 to 4.0 per 100,000 persons per year.6, 15, 16, 20 In North America, the reported incidence of collagenous colitis (3.1 and 4.6 per 100,000 per year) and of lymphocytic colitis (5.4
Mechanism of Diarrhea
A variety of mechanisms have been proposed to cause diarrhea in patients with microscopic colitis. The severity of diarrhea appears to be related to the intensity of the inflammatory response, as opposed to the thickness of the subepithelial collagen band, indicating that the diarrhea is predominantly inflammatory in origin.8, 39, 40, 41
Several studies have reported that patients with microscopic colitis have impaired electrolyte absorption or increased secretion.40, 42 Studies of epithelial
Pathogenesis
The etiology of microscopic colitis is unknown, but leading models of pathogenesis include autoimmunity, an immune or inflammatory response to luminal factors, and, for collagenous colitis, myofibroblast dysfunction.45 However, information on pathophysiology is taken from small, sometimes conflicting, studies and there is no single clear mechanism of disease.
Clinical Features
Microscopic colitis is characterized by chronic or intermittent watery diarrhea, ranging from mild and self-limited to severe, with dehydration and other metabolic abnormalities. Many patients also have abdominal pain or weight loss. The weight loss is typically mild but can be significant in some cases.26, 48 Quality of life is affected in proportion to the degree of diarrhea, abdominal pain, urgency, and incontinence.13, 97, 98 It is important to recognize that the symptoms of microscopic
Diagnosis
Endoscopic evaluation reveals that the colon is typically normal or has mild nonspecific changes such as erythema or edema. Colon ulceration is uncommon, and when it occurs it is likely to be caused by NSAIDs.118 Fecal leukocytes can be present,48 but steatorrhea, fever, or hematochezia indicate an alternate diagnosis should be made.
The hallmark histologic feature of microscopic colitis is intraepithelial lymphocytosis.2, 37 In addition, the disease is characterized by mixed infiltrate in the
Treatment
In treating patients with microscopic colitis, it is important that they first discontinue use of drugs that might have caused the disorder or other agents that might exacerbate diarrhea (eg, dairy products) if possible (Figure 6). Nonspecific antidiarrheal drugs such as loperamide or diphenoxylate/atropine can be effective15, 26, 48 and are often first prescribed for mild cases (Figure 6). If these agents are unsuccessful, or for patients with moderate symptoms, bismuth subsalicylate, at a
Summary
Microscopic colitis is a relatively common cause of chronic diarrhea, especially among the elderly, and the incidence is increasing. Biopsies of the colon are required to diagnose this disorder and should be performed for any patient undergoing sigmoidoscopy or colonoscopy to evaluate unexplained diarrhea. The 2 subtypes of microscopic colitis, collagenous and lymphocytic colitis, are similar histologically and clinically and seem to respond similarly to various medical therapies. Although
References (133)
- et al.
Microscopic colitis cases revisited
Gastroenterology
(1993) - et al.
Lymphocytic (”microscopic”) colitis: a comparative histopathologic study with particular reference to collagenous colitis
Hum Pathol
(1989) - et al.
Chronic diarrhea of unknown origin
Gastroenterology
(1980) - et al.
Chronic colitis with thickening of the subepithelial collagen layer (collagenous colitis): histopathologic findings in 15 patients
Hum Pathol
(1987) - et al.
Subepithelial collagen table thickness in colon specimens from patients with microscopic colitis and collagenous colitis
Gastroenterology
(1992) - et al.
Microscopic and collagenous colitis: different names for the same condition?
Gastroenterology
(1986) - et al.
Development of collagenous colitis in sequential biopsy specimens
Gastroenterology
(1984) - et al.
Incidence of collagenous and lymphocytic colitis: a 5-year population-based study
Am J Gastroenterol
(1999) - et al.
The prevalence, anatomic distribution, and diagnosis of colonic causes of chronic diarrhea
Gastrointest Endosc
(2000) - et al.
Usefulness of colonoscopy with biopsy in the evaluation of patients with chronic diarrhea
Am J Gastroenterol
(2001)
Microscopic colitis-defining incidence rates and risk factors: a population-based study
Clin Gastroenterol Hepatol
Collagenous and lymphocytic colitisevaluation of clinical and histological features, response to treatment, and long-term follow–up
Am J Gastroenterol
Microscopic colitis: a review
Am J Gastroenterol
Collagenous colitis in children
Gastroenterology
Resolution of collagenous colitis after treatment for Helicobacter pylori
Am J Gastroenterol
Mechanisms of diarrhea in collagenous colitis
Gastroenterology
Lymphocytic colitis: clinical features, treatment, and outcomes
Am J Gastroenterol
Anti-neutrophil cytoplasmic antibodies in ulcerative colitisComparison with other colitides/diarrheal illnesses
Gastroenterology
Patients with drug-induced microscopic colitis should not be included in controlled trials assessing the efficacy of anti-inflammatory drugs in microscopic colitis
Gastroenterology
Side effects of nonsteroidal anti-inflammatory drugs on the small and large intestine in humans
Gastroenterology
Lansoprazole-associated microscopic colitis: a case series
Am J Gastroenterol
Efficacy of open-label bismuth subsalicylate for the treatment of microscopic colitis
Gastroenterology
Effect of colonic perfusion with sulfated and nonsulfated bile acids on mucosal structure and function in the rat
Gastroenterology
Pitfalls in the diagnosis of collagenous colitis: experience with 75 cases from a registry of collagenous colitis at the Johns Hopkins Hospital
Hum Pathol
Fibrogenesis and fibrolysis in collagenous colitisPatterns of procollagen types I and IV, matrix-metalloproteinase-1 and -13, and TIMP-1 gene expression
Am J Pathol
Extracellular matrix composition and gene expression in collagenous colitis
Gastroenterology
Collagenous colitis: a clinicopathologic correlation
Mayo Clin Proc
Collagenous, microscopic and lymphocytic colitisAn evolving concept
Virchows Arch
’Collagenous colitis' with watery diarrhoea—a new entity?
Pathol Eur
Collagenous colitis in Orebro, Sweden, an epidemiological study 1984–1993
Gut
Lymphocytic (microscopic) colitisClinicopathologic study of 18 patients and comparison to collagenous colitis
Dig Dis Sci
Microscopic colitis syndrome
Gut
Lymphocytic colitis: clinical presentation and long term course
Gut
Colonic perforation in collagenous colitis: an unusual complication
Eur J Gastroenterol Hepatol
Microscopic colitis: a common diarrhoeal diseaseAn epidemiological study in Orebro, Sweden, 1993–1998
Gut
Lymphocytic colitis: a retrospective clinical study of 199 Swedish patients
Gut
Collagenous and lymphocytic colitis in Iceland
Dig Dis Sci
The epidemiology of microscopic colitis: a population based study in Olmsted County, Minnesota
Gut
Review article: drug-induced microscopic colitis—proposal for a scoring system and review of the literature
Aliment Pharmacol Ther
Collagenous colitis: a retrospective study of clinical presentation and treatment in 163 patients
Gut
Lymphocytic colitis in a pediatric patient: a possible adverse reaction to carbamazepine
Am J Gastroenterol
Microscopic colitis: a large retrospective analysis from a health maintenance organization experience
World J Gastroenterol
Collagenous and lymphocytic colitis: subject review and therapeutic alternatives
Am J Gastroenterol
Familial occurrence of microscopic colitis: a report on five families
Scand J Gastroenterol
Familial microscopic colitis
Can J Gastroenterol
Further report of familial occurrence of collagenous colitis
Scand J Gastroenterol
Cooccurrence of collagenous colitis with seronegative spondyloarthropathy: report of a case and literature review
J Rheumatol
Cancer risk in collagenous colitis
Inflamm Bowel Dis
Lymphocytic colitis: a distinct clinical entity?A clinicopathological confrontation of lymphocytic and collagenous colitis
Gut
Role of bile acids in lymphocytic colitis
Hepatogastroenterology
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Conflicts of interest The authors disclose no conflicts.