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Microscopic colitis

Microscopic colitis is a chronic inflammatory bowel disease characterized by inflammation of the colon's inner lining that appears normal to the naked eye but is detectable only through microscopic examination of tissue samples, leading primarily to persistent watery, nonbloody diarrhea.^[1]^[2]^[3] It encompasses two main subtypes—lymphocytic colitis, marked by an increased number of lymphocytes in the colon lining, and collagenous colitis, featuring a thickened layer of collagen beneath the lining—both of which share similar clinical features and management approaches despite distinct histological changes.^[1]^[2]^[3] The condition most commonly manifests with chronic watery diarrhea occurring multiple times daily, often accompanied by abdominal cramping, bloating, urgency, fecal incontinence, weight loss, nausea, and fatigue, though symptoms can fluctuate in intensity or occasionally resolve spontaneously.^[1]^[2]^[4] Unlike other inflammatory bowel diseases such as ulcerative colitis or Crohn's disease, microscopic colitis does not elevate the risk of colon cancer and primarily affects the colon without causing ulcers or structural damage visible on standard imaging.^[3] In the United States, as of 2021, it impacted approximately 700,000 individuals, with incidence rates increasing in recent decades; the average diagnosis age is 60 to 65 years.^[3]^[5] The exact cause of microscopic colitis remains unknown, but it is associated with immune system dysregulation, potentially triggered by factors such as certain medications (e.g., nonsteroidal anti-inflammatory drugs, proton pump inhibitors, or selective serotonin reuptake inhibitors), bacterial or viral infections, bile acid malabsorption, genetic predisposition, or autoimmune disorders like celiac disease or rheumatoid arthritis.^[1]^[2]^[4] Risk factors include being female (affected 3 to 9 times more often than males), advancing age over 50, current or past smoking, and a history of autoimmune conditions or family predisposition to gastrointestinal issues.^[1]^[3] Diagnosis typically involves colonoscopy with multiple biopsies from the colon to identify the microscopic inflammation, as routine blood tests, stool studies, or imaging may not reveal abnormalities.^[2]^[1] Treatment focuses on symptom relief and inflammation reduction, often beginning with lifestyle modifications such as a low-fat or low-fiber diet, avoidance of triggers like dairy or caffeine, and over-the-counter antidiarrheal agents like loperamide; for more severe cases, medications including budesonide (a corticosteroid with targeted colon effects), bismuth subsalicylate, or immunomodulators may be prescribed, with many patients achieving remission though flare-ups can recur.^[2]^[1] In some instances, symptoms improve upon discontinuing implicated medications or treating underlying conditions like celiac disease.^[1]^[4]

Overview

Definition and types

Microscopic colitis is a type of inflammatory bowel disease affecting the colon, characterized by chronic, nonbloody watery diarrhea in the presence of normal-appearing colonic mucosa on endoscopy or sigmoidoscopy, with inflammation detectable only through microscopic examination of biopsy samples.^[1]^[6] This condition is distinct from other forms of colitis due to the absence of visible endoscopic abnormalities, requiring histological analysis for diagnosis.^[2] The disease encompasses two primary subtypes: collagenous colitis and lymphocytic colitis, both sharing similar clinical features but differing in their microscopic pathology.^[7] Lymphocytic colitis is defined by a marked increase in intraepithelial lymphocytes, typically exceeding 20 per 100 epithelial cells, accompanied by mild chronic inflammation in the lamina propria but without significant subepithelial collagen deposition.^[6] In contrast, collagenous colitis features a thickened subepithelial collagen band, generally greater than 10 micrometers in thickness, along with an increased number of intraepithelial lymphocytes and surface epithelial damage.^[6]^[2] These histological hallmarks set microscopic colitis apart from macroscopic inflammatory bowel diseases such as ulcerative colitis or Crohn's disease, which exhibit overt endoscopic changes like mucosal friability, ulcers, or architectural distortion visible during routine examination.^[1]^[6] While both subtypes of microscopic colitis involve lymphocytic infiltration, the presence or absence of the collagenous band provides the key differentiating feature on biopsy.^[7]

Pathophysiology

Microscopic colitis is characterized by a dysregulated immune response in the colonic mucosa, primarily involving T-cell mediated inflammation triggered by luminal antigens or environmental factors such as medications. The influx of intraepithelial CD8+ T lymphocytes and increased CD3+ cells in the lamina propria suggests an aberrant activation of cell-mediated immunity, leading to chronic inflammation without gross mucosal ulceration. This process is thought to impair epithelial barrier function, potentially through mechanisms like neutrophil elastase-mediated disruption of E-cadherin junctions, which facilitates bacterial translocation and perpetuates the inflammatory cycle.^[8]^[9]^[8] Recent single-cell transcriptomic analyses as of 2025 have further elucidated these immune dynamics, revealing significant expansion of activated tissue-resident memory CD8+ T cells (Trm) with a cytotoxic phenotype (expressing GZMH) in microscopic colitis, driven by local T cell receptor (TCR) engagement and proliferation (MKI67 high expression). These CD8+ T cells show upregulated interferon-gamma (IFNG), interleukin-10 (IL10), and IL26, indicating a mix of pro- and anti-inflammatory roles. Enrichment of CD4+ regulatory T cells (Treg) and Th1 cells, along with myeloid remodeling including increased neutrophils, activated dendritic cells (LAMP3 high), and MMP12 high macrophages, underscores the complex local immune activation.^[10] Genetic predisposition plays a role in susceptibility, with the HLA ancestral 8.1 haplotype significantly associated with collagenous colitis but not lymphocytic colitis, indicating subtype-specific immune dysregulation. Environmental triggers, including nonsteroidal anti-inflammatory drugs (NSAIDs), proton pump inhibitors (PPIs), and selective serotonin reuptake inhibitors (SSRIs), are implicated in pathogenesis, possibly by altering the luminal microenvironment or directly stimulating immune responses in genetically susceptible individuals. Autoimmune mechanisms may contribute, as evidenced by the lack of specific autoantibodies but strong epidemiological links to other autoimmune disorders, supporting a hypothesis of immune cross-reactivity.^[9]^[8]^[8]^[9] Pathophysiological differences between subtypes highlight distinct inflammatory pathways. In collagenous colitis, fibroblast activation results in excessive subepithelial collagen deposition forming a band thicker than 10 μm, driven by transforming growth factor-β signaling and matrix remodeling, with a Th1/Tc1–Th17/Tc17 immune profile and genetic links to HLA-DRB1*03:01 (9.6% heritability). Lymphocytic colitis, conversely, features pronounced intraepithelial lymphocytosis (>20 lymphocytes per 100 epithelial cells) linked to T-cell dysregulation and higher expression of prostaglandin E receptor 4 (EP4), without significant collagenous changes, and a Th1/Th2 immune profile. Recent 2025 insights subclassify lymphocytic colitis into channelopathic (altered ion transport, possibly drug-induced) and inflammatory subtypes based on transcriptomics. Cytokine profiles underscore these distinctions; ex vivo studies of colonic biopsies from lymphocytic colitis patients show elevated pro-inflammatory cytokines such as TNF-α, IFN-γ, and IL-8, correlating with EP4 upregulation and suggesting a Th1/Th17-skewed response that amplifies epithelial damage. In vitro investigations further demonstrate that TNF-α induces IL-8 secretion in colonic epithelial cells, promoting neutrophil recruitment and barrier dysfunction in both subtypes. Diarrhea mechanisms differ: collagenous colitis involves water malabsorption (reduced aquaporin-8) and osmotic losses (downregulated SLC9A3/NHE3, SLC26A3/DRA), while lymphocytic colitis features increased paracellular/transcellular permeability (reduced aquaporins, claudins, ENaCγ). Microbiota alterations, such as reduced Ruminococcaceae and increased Epstein-Barr virus or Sutterella (in lymphocytic), are also implicated. Although dedicated animal models for microscopic colitis are limited, broader colitis models in mice reveal similar cytokine-driven mechanisms, with TNF-α blockade reducing inflammation and histological changes akin to those observed in human disease.^[8]^[11]^[11]^[12]

Clinical presentation

Signs and symptoms

The hallmark symptom of microscopic colitis is chronic, watery, non-bloody diarrhea, which affects nearly all patients. This diarrhea is typically persistent, with individuals experiencing more than three loose or watery stools per day, often accompanied by urgency and fecal incontinence. Nocturnal stools occur in about 50% of cases, and the symptom pattern is usually relapsing-remitting, with flares lasting days to weeks and periods of remission in 65–89% of patients. Accompanying gastrointestinal symptoms include abdominal cramping or pain (in approximately 50% of patients), bloating, and nausea. Patients may also experience weight loss due to malabsorption and dehydration from fluid loss, along with fatigue that contributes to overall debility. Unlike other forms of colitis, fever and bloody stools are rare. The relapsing nature of symptoms can be triggered by factors such as stress, which may exacerbate flares through its impact on hormone levels and gut function, or certain dietary elements like caffeine, alcohol, dairy, or gluten in susceptible individuals. These manifestations significantly impair quality of life, leading to risks of nutritional deficiencies, psychological effects such as anxiety, and disruptions in daily activities.

Associated conditions

Microscopic colitis (MC) is frequently associated with various autoimmune disorders, reflecting shared immunological pathways. Celiac disease exhibits a notable overlap with MC, with studies reporting a prevalence of 4-10% in MC patients and up to 10% of celiac patients developing MC.00667-3/fulltext) Autoimmune thyroiditis is another common comorbidity, observed in approximately 20% of MC cases in cohort studies.^[13] Rheumatoid arthritis and primary biliary cholangitis also show increased co-occurrence with MC, with autoimmune conditions overall present in up to 53% of collagenous colitis patients.^[14]^[15] Beyond autoimmune diseases, MC is linked to metabolic conditions such as type 2 diabetes and hypertension, which are more prevalent among MC patients compared to the general population.^[16] A potential connection exists with Parkinson's disease, where MC may co-occur as a comorbidity or develop following a PD diagnosis, though it does not appear to increase PD risk.^[17] Certain medications are associated with an elevated risk of MC onset, particularly with long-term use. Nonsteroidal anti-inflammatory drugs (NSAIDs) and proton pump inhibitors (PPIs) have been shown to increase MC risk, with concomitant use potentially amplifying this effect; for instance, recent or prolonged exposure to these agents correlates with higher incidence rates.^[18] Statins likewise demonstrate a positive association, though evidence is mixed in older adults where medications may not be primary triggers.^[19] Bidirectional relationships are evident in some associations, notably with celiac disease; implementing a strict gluten-free diet to manage celiac disease can alleviate MC symptoms in overlapping cases, particularly when MC contributes to refractory diarrhea in celiac patients.00667-3/fulltext)

Diagnosis

Clinical evaluation

The clinical evaluation of suspected microscopic colitis begins with a detailed patient history, emphasizing the hallmark symptom of chronic watery, nonbloody diarrhea lasting more than four weeks.^[20]^[21] Key aspects include inquiring about recent travel, antibiotic use, or exposure to potential infectious agents to exclude acute or chronic infections, as well as assessing family history of autoimmune conditions like celiac disease or inflammatory bowel disease.^[22]^[23] A thorough medication review is essential, focusing on drugs associated with increased risk, such as proton pump inhibitors, nonsteroidal anti-inflammatory drugs, selective serotonin reuptake inhibitors, and statins.^[20]^[21] Physical examination typically reveals normal findings in most cases, but clinicians should assess for signs of dehydration (e.g., dry mucous membranes, orthostatic hypotension), mild abdominal tenderness, or evidence of nutritional deficits such as weight loss or muscle wasting, particularly in elderly patients with prolonged symptoms.^[22]^[23] These findings, when present, help gauge disease severity and guide supportive care during evaluation.^[21] Initial laboratory tests are aimed at ruling out alternative causes and assessing complications. Stool studies should include testing for pathogens such as Clostridium difficile, ova and parasites, and Giardia via immunoassay, along with fecal calprotectin to evaluate for inflammation (though it has limited diagnostic utility in microscopic colitis) and fecal elastase to screen for exocrine pancreatic insufficiency.^[20]^[22] Blood tests routinely comprise a complete blood count to detect anemia or leukocytosis, serum electrolytes to identify imbalances from diarrhea, C-reactive protein for systemic inflammation, and celiac disease serology (e.g., IgA tissue transglutaminase antibodies) given the association with microscopic colitis.^[21]^[23] Endoscopy plays a pivotal role in the evaluation, with colonoscopy or flexible sigmoidoscopy recommended to exclude macroscopic colonic lesions suggestive of other conditions like inflammatory bowel disease or malignancy.^[22]^[23] The colonic mucosa typically appears normal or near-normal during the procedure, necessitating multiple random biopsies (at least two to four from the right and left colon) from unaffected areas to obtain tissue for histopathological analysis.^[20]^[21] This approach ensures comprehensive assessment, as the diagnosis relies on microscopic findings rather than gross abnormalities.^[22]

Histopathology

Microscopic colitis is definitively diagnosed through histopathological examination of colonic mucosal biopsies obtained during endoscopy, revealing characteristic inflammatory changes not visible macroscopically.^[24] The two main subtypes, lymphocytic colitis and collagenous colitis, are distinguished by specific microscopic features, including the density of intraepithelial lymphocytes and the presence of a subepithelial collagen band.^[25] These findings must be interpreted in the context of clinical symptoms, as similar histological patterns can occur in other conditions.^[26] Lymphocytic colitis is characterized by an increased number of intraepithelial lymphocytes exceeding 20 per 100 surface epithelial cells, typically assessed using immunohistochemical staining for CD3-positive T cells if needed.^[25] Accompanying features include surface epithelial damage such as flattening, mucin depletion, and cuboidal changes, along with a lymphoplasmacytic infiltrate in the lamina propria but minimal or no crypt architectural distortion.^[27] The inflammation is often superficial, with preserved overall crypt architecture distinguishing it from more severe colitides.^[28] In collagenous colitis, the hallmark is a thickened subepithelial collagen band measuring greater than 10 μm in thickness, best visualized with a trichrome stain to confirm the collagen deposition and entrapment of capillaries or fibroblasts.^[29] This is accompanied by a mixed lymphoplasmacytic infiltrate in the lamina propria and surface epithelial injury similar to lymphocytic colitis, but with fewer intraepithelial lymphocytes (usually <20 per 100 epithelial cells) and minimal crypt distortion.^[24] The collagen band may show variability in thickness across biopsies, occasionally leading to a diagnosis of incomplete collagenous colitis if borderline.^[26] Due to the patchy distribution of histological changes in microscopic colitis, biopsies should be obtained from multiple sites, including both the right (ascending) and left (descending or sigmoid) colon, with at least two biopsies per site recommended for optimal diagnostic yield.^[30] Sampling the rectosigmoid alone is insufficient, as it may miss lesions, and right-sided biopsies are particularly important for lymphocytic colitis.^[30] If the terminal ileum is intubated, biopsies are typically normal, as small bowel involvement is rare and not a defining feature.^[25] The severity of inflammation in microscopic colitis can be assessed using standardized histological scoring systems adapted from those for inflammatory bowel disease, such as the Geboes index, which evaluates chronic inflammatory infiltrates, epithelial damage, and crypt changes on a graded scale.^[31] These scales, including variations like the Nordic-adapted approaches in multicenter studies, help quantify lamina propria inflammation (mild to severe) and intraepithelial lymphocytosis for research and prognostic purposes, though routine clinical use focuses primarily on meeting diagnostic thresholds.^[32]

Differential diagnosis

The differential diagnosis of microscopic colitis primarily involves other causes of chronic watery, nonbloody diarrhea, requiring careful clinical, laboratory, and histopathological evaluation to exclude mimics.^[8] Irritable bowel syndrome (IBS) is a common functional disorder that overlaps symptomatically but lacks colonic inflammation; it is distinguished by normal fecal calprotectin levels (typically <50 μg/g), absence of histological changes, improvement with fasting, and fulfillment of Rome IV criteria without alarm features.^[8]^[33] Celiac disease affects the small bowel and may coexist with microscopic colitis but is identified through positive serology (e.g., anti-tissue transglutaminase antibodies) and duodenal biopsy showing villous atrophy, often with associated malabsorption or nutritional deficiencies not typical in isolated microscopic colitis.^[9]^[8] Bile acid malabsorption frequently coexists (up to 44% of cases) or mimics symptoms and is differentiated by a positive response to bile acid sequestrants like cholestyramine or abnormal SeHCAT scintigraphy (selenium-75-homocholic acid taurine retention <15% at 7 days).^[8]^[9] Infectious colitis, such as Clostridium difficile-associated or other pathogen-related (e.g., post-travel), presents with more acute onset, recent antibiotic exposure, or fever, and is excluded via stool studies identifying organisms, unlike the chronic course and negative cultures in microscopic colitis.^[8]^[34] Drug-induced diarrhea While some medications can cause noninflammatory diarrhea that resolves upon discontinuation and lacks histological changes of inflammation, others such as proton pump inhibitors, nonsteroidal anti-inflammatory drugs, and selective serotonin reuptake inhibitors are associated with microscopic colitis, featuring the characteristic intraepithelial lymphocytosis or subepithelial collagen band, and symptoms may improve with drug cessation.^[24] Early inflammatory bowel disease (IBD), such as ulcerative colitis or Crohn's disease, may mimic with subtle endoscopic changes but features markedly elevated fecal calprotectin (>250 μg/g), bloody stools, and histopathological findings like crypt architectural distortion, cryptitis, or granulomas, contrasting the preserved crypt architecture and milder calprotectin elevation (mean ~214 μg/g) in microscopic colitis.^[33]^[34]^[9] Rare mimics include ischemic colitis, which has acute abdominal pain, affects watershed areas, and shows hyalinized lamina propria, crypt atrophy, and vascular congestion on biopsy, differing from the diffuse, chronic pattern in microscopic colitis.^[34] Radiation-induced colitis occurs in patients with pelvic radiation history, featuring crypt distortion, nuclear atypia, and eosinophilic infiltrates on histology, unlike the uniform inflammatory changes without atypia in microscopic colitis.^[34]

Management

Pharmacological treatment

The pharmacological treatment of microscopic colitis focuses on inducing clinical remission, alleviating symptoms, and preventing relapse through anti-inflammatory agents and supportive therapies. First-line therapy is budesonide, a second-generation glucocorticoid with high topical anti-inflammatory activity in the colon due to its low systemic bioavailability (<10%). It is typically administered at a dose of 9 mg/day for 6–8 weeks, followed by gradual tapering to minimize side effects such as adrenal suppression. Systematic reviews report clinical response rates exceeding 80% (95% CI 0.74–0.89), with histological improvement in the majority of cases, making it effective for both collagenous and lymphocytic subtypes.^[21] For patients with milder symptoms or as adjunctive measures, second-line options include antidiarrheals like loperamide (up to 16 mg/day), which slow intestinal motility and achieve symptom relief in approximately 62% of cases (95% CI 0.43–0.80). Bile acid sequestrants such as cholestyramine (4–24 g/day) address diarrhea potentially exacerbated by bile acid malabsorption, with response rates around 60% (95% CI 0.51–0.68). Immunomodulators, including prolonged-release formulations of budesonide at maintenance doses of 3–6 mg/day, are used to sustain remission, particularly given relapse rates of 50–88% upon discontinuation of induction therapy.^[21]^[35]^[36] In refractory cases unresponsive to budesonide, off-label use of azathioprine (2–2.5 mg/kg/day) or mercaptopurine provides immunosuppression with response rates of about 49% (95% CI 0.27–0.71), often for long-term maintenance. Biologic therapies, such as anti-TNF agents (e.g., infliximab or adalimumab) and vedolizumab, are reserved for steroid-dependent or refractory disease, demonstrating clinical benefit in 73% of cases (95% CI 0.63–0.83 for anti-TNF; 0.57–0.87 for vedolizumab), with potentially better responses observed in lymphocytic colitis compared to collagenous colitis. These agents target gut-specific inflammation, offering a tolerable safety profile in specialized settings. As of 2025, up to 80% of patients may relapse upon budesonide discontinuation, with biologics recommended for the approximately 7% refractory to standard therapy.^[21]^[37]^[38] While medications such as nonsteroidal anti-inflammatory drugs (NSAIDs) and proton pump inhibitors (PPIs) have been historically associated with up to 20–30% of cases and potentially implicated in onset or relapse, a 2025 nationwide study of over 2.8 million older adults found no evidence of causality for these or other common drugs like SSRIs. Discontinuation may be considered on a case-by-case basis if symptoms improve upon withdrawal, but is not routinely recommended based on current evidence. Patients should be monitored clinically for symptom recurrence post-withdrawal, with alternative therapies considered if necessary to avoid rebound effects.^[35]^[21]^[39]

Non-pharmacological approaches

Non-pharmacological approaches to managing microscopic colitis focus on lifestyle adjustments that can alleviate symptoms such as chronic watery diarrhea and abdominal discomfort, particularly during flares. These strategies aim to support gastrointestinal function, prevent dehydration, and identify personal triggers without relying on medications. Evidence indicates that such interventions can improve quality of life, though they are most effective when tailored to individual needs and combined with medical oversight.^[40] Dietary modifications play a central role in symptom control, with recommendations emphasizing hydration and avoidance of potential irritants. Patients are advised to maintain adequate fluid intake, prioritizing water and electrolyte-rich options to counteract diarrhea-induced dehydration, while limiting caffeine and alcohol, which may exacerbate symptoms. A short-term low-fat, low-fiber diet can help reduce diarrhea severity by easing digestive workload, incorporating soft foods like bananas, rice, and applesauce. For those with overlapping conditions such as celiac disease, gluten-free diet trials may be beneficial due to the established association between microscopic colitis and celiac disease, though gluten intake alone does not appear to increase risk in the absence of celiac disease. Low-FODMAP diet trials are sometimes suggested as an elimination approach to identify fermentable carbohydrate triggers, particularly in cases mimicking irritable bowel syndrome symptoms.^[35]^[40]^[35]^[41]^[42]^[2] Smoking cessation is a key preventive measure, as active smoking is linked to an increased risk of developing microscopic colitis and poorer response to treatments. Studies show that the risk diminishes following quitting, with higher pack-years correlating to greater odds of disease onset. Advising patients to stop smoking is recommended as a first-line lifestyle change to potentially reduce symptom frequency and severity.^[43]^[43]^[9] Supplements like fiber and bismuth subsalicylate offer supportive options for mild cases, focusing on stool bulking and anti-inflammatory effects. Psyllium, a soluble fiber supplement, helps form bulkier stools to alleviate diarrhea without addressing underlying inflammation. Bismuth subsalicylate, taken for up to 8 weeks, has demonstrated efficacy in reducing diarrhea and histological inflammation in open-label studies. Probiotics have shown limited benefit, with guidelines suggesting against their routine use for inducing remission due to insufficient evidence from randomized trials. Patient education on avoiding personal triggers, such as dairy or artificial sweeteners in cases of intolerance, is essential for long-term management.^[2]^[44]70629-8/fulltext)^[45] Multidisciplinary care enhances overall support, involving dietitians to customize nutritional plans and psychologists to address psychological distress from symptoms like fecal incontinence. Anxiety and social withdrawal are common in microscopic colitis, particularly with incontinence-related embarrassment, and cognitive behavioral interventions can mitigate these impacts. Such team-based approaches, adapted from broader inflammatory bowel disease models, improve patient adherence and outcomes.^[46]^[47]^[48]

Prognosis and complications

Prognosis

Microscopic colitis is characterized by a chronic relapsing-remitting course, with most patients achieving clinical remission following appropriate treatment, though relapses are common upon discontinuation of therapy. Studies indicate that approximately 75-80% of patients experience prolonged remission over 5-8 years of follow-up, defined as absence of symptoms without ongoing medication. However, relapse rates range from 50% to 80% within 1-3 years after stopping treatment, with a median time to relapse of about 39 days to 3.9 years.^[49]^[50]^[51]^[21] Several factors influence prognosis, including early diagnosis, which is associated with better long-term outcomes by enabling prompt intervention. Refractory disease, unresponsive to first-line therapies like budesonide, occurs in 10-20% of cases and is more prevalent in the collagenous subtype compared to lymphocytic colitis. Additional risk factors for relapse include advanced age over 60 years, symptom duration exceeding 12 months prior to treatment, high baseline stool frequency, and ongoing smoking.^[47]^[52]^[47]^[53] Remission can be maintained through long-term low-dose budesonide or lifestyle modifications such as smoking cessation, which reduce flare frequency. Progression to inflammatory bowel disease is rare, occurring in fewer than 10% of cases.^[7]^[54] Most patients with microscopic colitis manage symptoms effectively with treatment, leading to improved quality of life, though some experience persistent issues like abdominal pain and fatigue even in clinical remission. The condition carries a low but slightly increased all-cause mortality risk compared to the general population (HR ≈1.2-1.5), primarily due to gastrointestinal infections and cardiovascular events.^[55]^[56]^[57]^[58]

Complications

Microscopic colitis, characterized by chronic watery diarrhea, can lead to acute complications primarily from fluid and electrolyte losses. Severe dehydration occurs due to persistent nonbloody diarrhea, potentially requiring hospitalization for fluid replacement. Electrolyte imbalances, such as hypokalemia, arise from excessive fecal potassium loss, contributing to muscle weakness and cardiac arrhythmias if untreated. In severe cases, these imbalances and dehydration can precipitate acute kidney injury through prerenal azotemia, as reported in patients with collagenous colitis subtype. Patients with microscopic colitis have an increased risk of major adverse cardiovascular events (aHR 1.28), potentially linked to chronic inflammation or comorbidities.^[59]^[60]^[61]^[62] Chronic complications stem from prolonged symptoms and treatment effects. Osteoporosis risk increases twofold in microscopic colitis patients, attributable to chronic diarrhea-induced losses of calcium and vitamin D, as well as potential malabsorption. Long-term corticosteroid use, such as budesonide for disease management, further elevates this risk through bone mineral density reduction. Vitamin deficiencies, including vitamin D and occasionally B12, may develop from ongoing diarrhea impairing nutrient absorption, leading to fatigue and bone health issues. Fecal incontinence, a common sequela of urgency and frequent stools, can cause perianal skin breakdown and irritation due to repeated exposure to moisture and fecal enzymes.^[63]^[64]^[65]^[66]^[67] Rare severe outcomes include toxic megacolon, exceptionally reported in collagenous colitis cases, presenting as colonic dilation with systemic toxicity. Regarding colorectal cancer, microscopic colitis is associated with no increased risk and possibly a reduced incidence of adenomas and carcinomas compared to the general population, distinguishing it from inflammatory bowel diseases. Management of complications involves electrolyte monitoring and correction with intravenous fluids or supplements during acute episodes, alongside bone density screening via dual-energy X-ray absorptiometry for at-risk patients to guide preventive therapy like bisphosphonates or calcium/vitamin D supplementation. Unlike complications in inflammatory bowel disease, those in microscopic colitis are generally milder and reversible with prompt intervention.^[68]^[69]^[70]^[71]^[64]

Epidemiology

Incidence and prevalence

Microscopic colitis affects a relatively small but growing proportion of the population worldwide, with pooled incidence rates of approximately 11 cases per 100,000 person-years (95% CI 9-14).^[72] Prevalence figures vary by region and time but are generally reported between 100 and 220 cases per 100,000 individuals, with a pooled estimate of 119 per 100,000 (95% CI 73-166), reflecting underdiagnosis in earlier decades and recent increases; in the United States, approximately 700,000 individuals are affected (~212 per 100,000).^[72]^[3] These rates position microscopic colitis as an important cause of chronic diarrhea, particularly in older adults, though it remains less common than other inflammatory bowel diseases like ulcerative colitis in many regions.^[5] Geographic variations are notable, with higher incidence and prevalence observed in Northern Europe compared to other areas. In Sweden, for instance, the prevalence has been estimated at around 49 cases per 100,000 for collagenous colitis, a subtype, while overall rates in the country reach up to 10.5 cases per 100,000 person-years (2006-2015).^[73] In contrast, reporting from Asia indicates lower incidence, potentially due to diagnostic challenges and lower biopsy rates, with studies suggesting rates below 2 cases per 100,000 person-years in countries like Malaysia and India.^[74] These differences may stem from environmental, genetic, or healthcare access factors, though data from Asia remain limited.^[32] Among subtypes, collagenous colitis is slightly more common, accounting for approximately 55% of cases, compared to 45% for lymphocytic colitis, based on pooled data from population-based studies.^[34] Incidence trends show a clear increase over time, with some cohorts reporting up to a 10-fold rise since 2001, attributed to aging populations, increased use of implicated medications such as proton pump inhibitors, and improved diagnostics, as evidenced by studies in Denmark, the UK, and the US as of 2022.^[9]

Risk factors and demographics

Microscopic colitis predominantly affects older adults, with peak onset occurring between the ages of 60 and 70 years. The condition is rare in children and young adults under 30 years of age. It exhibits a strong female predominance, with female-to-male ratios ranging from 2:1 for lymphocytic colitis to as high as 9:1 for collagenous colitis overall. Postmenopausal status in women is associated with increased risk, potentially linked to hormonal factors.^[75]^[76]^[77] Among unmodifiable risk factors, Northern European ancestry correlates with higher disease occurrence, as evidenced by elevated rates in Scandinavian populations such as those in Denmark and Sweden. Family history plays a role, with familial clustering suggesting a genetic component, including shared human leukocyte antigen associations and overlap with inflammatory bowel disease genetics.^[78]^[79] Modifiable risk factors include current cigarette smoking, which confers a 2- to 4-fold increased odds in a dose-dependent manner that diminishes after cessation. Long-term use of nonsteroidal anti-inflammatory drugs (NSAIDs) and proton pump inhibitors (PPIs) is linked to elevated odds ratios of 2 to 5. Excess alcohol consumption also heightens risk, with odds approximately 1.6 times higher among consumers compared to non-consumers.^[80]^[81]^[82] Notable interactions exist between risk factors. Breastfeeding in infancy may exert a protective influence, consistent with patterns observed in related autoimmune conditions.^[83]

History

Discovery and classification

Collagenous colitis was independently described in 1976 by Swedish pathologist Carl-Göran Lindström and by Freeman et al., who reported cases of chronic watery diarrhea with a distinctive subepithelial collagen band in colonic biopsies, initially termed "collagenous colitis."^[84]^[26] This finding distinguished it from other known forms of colitis, though its clinical significance remained unclear at the time. In 1980, Read and colleagues introduced the term "microscopic colitis" to describe patients with chronic diarrhea and normal endoscopic appearances but subtle inflammatory changes visible only on histology, encompassing cases that overlapped with Lindström's description.^[85] During the 1980s, microscopic colitis began to be recognized as a distinct entity from inflammatory bowel disease (IBD), as histopathological studies highlighted its unique features, such as increased intraepithelial lymphocytes without crypt distortion or granulomas typical of IBD.^[85] In 1989, Lazenby et al. provided a seminal comparative histopathologic analysis, formally describing lymphocytic colitis as a separate subtype characterized by prominent intraepithelial lymphocytosis (>20 lymphocytes per 100 epithelial cells) in the absence of a thickened collagen band.^[86] This work clarified the overlap and differences between the two forms, solidifying their classification. The 1990s saw key milestones in histopathological standardization, with consensus criteria established for diagnosing the subtypes based on biopsy features, including lymphocyte counts and collagen thickness measurements, which improved diagnostic reproducibility.^[85] By 2000, microscopic colitis was firmly separated into its two main subtypes—collagenous and lymphocytic—based on these refined criteria, facilitating more accurate identification.^[85] Early challenges included frequent misdiagnosis as irritable bowel syndrome (IBS) due to the normal macroscopic appearance on endoscopy and overlapping symptoms of chronic watery diarrhea.^[87]

Recent developments

Recent genetic research has advanced the understanding of microscopic colitis through genome-wide association studies (GWAS). A 2024 meta-analysis of GWAS data from 1498 patients with collagenous colitis, 373 with lymphocytic colitis, and 13,487 controls identified strong associations with human leukocyte antigen (HLA) alleles, particularly HLA-DRB103:01 as a key risk factor for collagenous colitis and HLA-DRB104:01 showing a protective effect.^[88] These findings highlight immune-mediated mechanisms and subtype-specific genetic signatures in the pathogenesis of microscopic colitis.^[88] Studies on the gut microbiome have revealed distinct alterations in patients with microscopic colitis. Fecal analyses from 2025 research demonstrated shifts in microbial composition and metabolome profiles, with reduced diversity and enrichment of certain pathobionts compared to healthy controls, suggesting a role in disease onset and persistence.^[89] These microbiome changes have spurred interest in targeted therapies, including a 2023 pilot trial evaluating oral fecal microbiota transplantation capsules for active microscopic colitis, which showed preliminary promise in refractory cases by restoring microbial balance.^[90] Therapeutic guidelines updated in 2024 reinforce budesonide as the first-line treatment for microscopic colitis, with recommendations for 9 mg daily for 6-8 weeks to induce remission, followed by maintenance dosing to prevent relapse in responsive patients.^[91] For budesonide-refractory cases, emerging data from 2024 support the use of biologics like vedolizumab and Janus kinase inhibitors such as upadacitinib, based on case series and small studies demonstrating sustained remission.^[92] A 2025 systematic review and meta-analysis confirmed the rising incidence of microscopic colitis, attributing part of the increase to widespread proton pump inhibitor (PPI) use, which carries a four-fold higher odds of disease development through mechanisms like gut dysbiosis.^[93] Diagnostic approaches have evolved with improved algorithms, incorporating artificial intelligence for histopathologic analysis to enhance accuracy in identifying lymphocytic infiltrates and collagen bands.^[94] Emerging concepts point to environmental triggers, including viral infections. Reports from 2022-2025 document cases of microscopic colitis onset following SARS-CoV-2 infection, suggesting post-COVID immune dysregulation as a potential initiator, particularly in lymphocytic and collagenous subtypes.^[95] Subtype-specific biologics remain in early investigation, with phase II trials exploring anti-integrin therapies for refractory collagenous colitis to target immune cell trafficking.^[92]

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Microscopic colitis: Etiopathology, diagnosis, and rational ... - eLife
Aug 1, 2022 · Microscopic colitis is an inflammatory bowel disease divided into two subtypes: collagenous colitis and lymphocytic colitis.
[9]
Lymphocytic Colitis Is Associated with Increased Pro-Inflammatory ...
This is the first report to demonstrate that LC is associated with increased TNF-α, INF-γ and IL-8 concurrent with a marked up-regulation of EP4.
[10]
P238 Autoimmune comorbidities in microscopic colitis
Jan 24, 2024 · 20 patients (21.3 %) had autoimmune thyroiditis, 7 (7.4 %) had coeliac disease, 7 (7.4 %) had autoimmune skin conditions, 5 (5.3 %) had ...
[11]
Rheumatologic associations of microscopic colitis: A narrative review
Apr 13, 2023 · The identification of rheumatoid arthritis and limited scleroderma as comorbidities with MC was noteworthy. Inflammatory arthropathy was ...
[12]
Dissecting Microscopic Colitis Immunopathophysiology - NIH
Microscopic colitis is an inflammatory bowel disease (IBD) comprising two ... primary biliary cholangitis [9, 10, 11]. In comparison with other ...
[13]
Patients With Microscopic Colitis Are at Higher Risk of Major ...
Comorbidities, including diabetes, obesity, hypertension, dyslipidemia, chronic kidney disease, and celiac disease, were more prevalent in MC patients than in ...
[14]
Association Between Microscopic Colitis and Parkinson's Disease in ...
Mar 25, 2021 · Our findings suggest that MC may not be a risk factor for PD; instead, it may co-occur with PD as a comorbidity or develop after a diagnosis of PD.
[15]
Are Drugs Associated with Microscopic Colitis? A Systematic ...
Dec 29, 2022 · PPIs, NSAIDs, SSRIs, and Statins are associated with an increased risk of MC compared to the random control group.
[16]
Are Drugs Associated with Microscopic Colitis? A Systematic ...
Dec 29, 2022 · PPIs, NSAIDs, SSRIs, and Statins are associated with an increased risk of MC compared to the random control group. On the contrary, the use of ...
[17]
https://pubmed.ncbi.nlm.nih.gov/33764622/
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Diagnosis and Pharmacological Management of Microscopic Colitis ...
Jan 17, 2024 · Microscopic colitis, a diagnosis under the umbrella term of inflammatory bowel disease, is a prevalent cause of watery diarrhea, often with ...
[19]
Microscopic colitis - Symptoms, diagnosis and treatment
Aug 22, 2023 · Diagnosis of microscopic colitis is confirmed by the presence of characteristic pathohistologic findings from ileocolonoscopy biopsies taken ...History And Exam · Diagnostic Tests · Contributors
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Microscopic (lymphocytic and collagenous) colitis
Sep 10, 2025 · Microscopic (lymphocytic and collagenous) colitis: Clinical manifestations, diagnosis, and management - UpToDate.
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Collagenous and Lymphocytic Colitis - StatPearls - NCBI Bookshelf
Sep 12, 2022 · Histopathology · Collagenous colitis: A collagen band greater than 10 micrometers in diameter in the subepithelial layer defines this type of ...Continuing Education Activity · Histopathology · Evaluation · Differential Diagnosis
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Colon - Lymphocytic colitis - Pathology Outlines
Jun 4, 2021 · Lymphocytic colitis · Normal colonoscopy or mild nonspecific erythema or edema · Biopsies from all segments of the colon, proximal to rectosigmoid.
[23]
Microscopic Colitis (Collagenous and Lymphocytic Colitis)
Mar 25, 2021 · Microscopic colitis (MC) is a chronic inflammatory condition of the colon, predominantly subdivided into collagenous colitis (CC) and lymphocytic colitis (LC).
[24]
Microscopic Colitis: Pathogenesis and Diagnosis - MDPI
The following studies provide more information on the association of microscopic colitis with bile acid malabsorption and/or treatment of patients with ...Missing: biliary cholangitis
[25]
The subtypes of microscopic colitis from a pathologist's perspective
Microscopic colitis (MC) is a chronic inflammatory bowel disease including the morphological subtypes collagenous colitis (CC) (Figure 1) and lymphocytic ...Missing: authoritative sources
[26]
Colon - Collagenous colitis - Pathology Outlines
Aug 3, 2020 · Form of microscopic colitis clinically associated with chronic watery diarrhea and histologically characterized by colonic intraepithelial lymphocytosis.
[27]
Analysis of Clinical and Histopathological Findings in Microscopic ...
In MC, the morphologic findings may be patchy and not continuous. To achieve an accurate diagnosis, biopsies of the right and left colon are recommended; if ...
[28]
Histologic scoring indices for evaluation of disease activity in ...
The Geboes Score, a commonly used histologic index for UC, was developed in 2000 using a multivariate regression model which resulted in an index composed of ...
[29]
Prevalence, Pathogenesis, Diagnosis, and Management of ...
Jul 4, 2017 · This review article outlines the risk factors associated with MC, the clinical presentation, diagnosis and histologic findings, as well as a proposed treatment ...
[30]
Fecal calprotectin level in microscopic colitis: a systematic review ...
Jun 14, 2023 · Fecal calprotectin (FCP) is often measured in patients with suspected IBD and is used for diagnosis and disease monitoring. It can be used to ...
[31]
Microscopic Colitis: A Review of the Literature and Histopathologic ...
Apr 24, 2025 · The diagnosis of microscopic colitis is largely one of exclusion, where the initial clinical differential may include infectious etiologies, ...Incidence And Clinical... · Radiation Colitis · Ischemic Colitis
[32]
Medication use and microscopic colitis - PMC - PubMed Central
Microscopic colitis is an increasingly common cause of watery diarrhea. Several classes of medications have been associated with microscopic colitis in prior ...
[33]
Microscopic colitis - Diagnosis and treatment - Mayo Clinic
Jan 16, 2024 · Microscopic colitis may get better on its own. But when symptoms are severe or don't go away, you may need treatment to relieve them. ...Diagnosis · Treatment · Preparing For Your...Missing: definition | Show results with:definition
[34]
Effectiveness and Safety Profile of Budesonide Maintenance in ...
Jul 3, 2024 · Conclusions: Budesonide is an effective maintenance treatment for MC. There is a high risk of recurrence after budesonide discontinuation, but ...Missing: release | Show results with:release<|control11|><|separator|>
[35]
Efficacy and Safety of Vedolizumab and Tumor Necrosis Factor ...
Sep 1, 2024 · Vedolizumab and anti-TNF-α agents demonstrated a clinical benefit in the treatment of steroid-refractory microscopic colitis and with a tolerable safety ...
[36]
Eating, Diet, & Nutrition for Microscopic Colitis - NIDDK
Scientists have not yet discovered dietary changes that heal microscopic colitis. However, in some cases, doctors may recommend changing what you eat and drink.
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The association between microscopic colitis and celiac disease
In summary, our meta-analysis confirms a statistically significant association between CD and MC, with a high prevalence of CD in both subtypes of MC.
[38]
Dietary Gluten Intake and Risk of Microscopic Colitis Among ... - NIH
Conclusion: Dietary gluten intake during adulthood was not associated with risk of microscopic colitis among women without celiac disease.
[39]
Smoking is Associated with an Increased Risk of Microscopic Colitis
Apr 27, 2018 · Risk of microscopic colitis appeared to increase with higher pack-years and diminish following smoking cessation.
[40]
What is Microscopic Colitis? | Crohn's & Colitis Foundation
Microscopic colitis treatment and therapy Treatment generally starts with bulk-forming agents such as psyllium (Metamucil®), or various antidiarrheals that act ...Missing: probiotics | Show results with:probiotics
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Medical management of microscopic colitis
Nov 13, 2015 · In patients with symptomatic microscopic colitis, AGA recommends treatment with budesonide over no treatment for the induction of clinical remission.Missing: evaluation diagnosis
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Inflammatory Bowel Disease Care: “It Takes a Village” - Consult QD
Oct 26, 2019 · ... psychologists, colorectal surgeons, pain specialists, pharmacists, dietitians and more. ... Many patients travel long distances to receive IBD ...
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Microscopic colitis in older adults: impact, diagnosis, and management
Jul 5, 2022 · The hallmark symptom is in most cases profuse, nonbloody diarrhea, with a detrimental impact on the patient's subjective quality of life.Epidemiology, Risk Factors... · Diagnosis · Management
[44]
Microscopic colitis: Struggling with an invisible, disabling disease
May 15, 2019 · Living with MC creates worry and has a psychological impact. Even when in remission, an undercurrent of anxiety and worry related to bowel ...
[45]
Long-Term Natural History of Microscopic Colitis: A Population ... - NIH
Sep 3, 2019 · This population-based study showed that after diagnosis, two-third of the patients with MC observed long-term clinical remission. Age at ...Missing: prognosis | Show results with:prognosis
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Prevalence and Natural History of Microscopic Colitis - PubMed
After a follow-up of 7.8±0.38 years from diagnosis, 75% of the patients experienced prolonged disease remission, defined as clinical remission without requiring ...
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Microscopic colitis: A review of etiology, treatment and refractory ...
Clinical remission rate after induction period was 84.5% and the median time to remission was 10.5 d[16]. Similar randomized controlled trials comparing ...
[48]
A Literature Review of Microscopic Colitis - PMC - NIH
Jan 24, 2024 · Although budesonide is an effective treatment in most cases, budesonide-refractory MC represents a significant clinical challenge. ... Up to 10-20 ...
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Optimal management of collagenous colitis: a review - PMC - NIH
Feb 10, 2016 · 80 The rate of relapse was 61%. Risk factors associated with relapse included high-stool frequency at baseline and a long duration of diarrhea.Collagenous Colitis · Treatment · Refractory Cc
[50]
Insights into the underlying mechanisms and clinical management of ...
The transformation of IBD to MC may then be triggered by certain risk factors such as MC-related drug use, infection, and mechanistically may be due to an ...
[51]
Long-term prognosis of clinical symptoms and health-related quality ...
Conclusions: Although considered to be in clinical remission, patients with microscopic colitis suffer from persisting symptoms such as abdominal pain, fatigue ...
[52]
Microscopic Colitis: An Underestimated Disease of Growing ... - NIH
Although microscopic colitis is a chronic inflammatory condition, it does not directly result in an increased risk of mortality or an elevated risk of ...
[53]
Microscopic Colitis: A Review Article - PMC - NIH
Oct 16, 2023 · MC is a gastrointestinal condition distinguished by gastroenterologists in their practice and characterized mainly by chronic persistent watery diarrhea.
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Microscopic colitis: Common cause of unexplained nonbloody ... - NIH
If treatment was continued over 6 mo, clinical and histological remission was achieved in 85% of those with lymphocytic and 91% of those with collagenous ...Microscopic Colitis: Common... · Etiopathogenesis · Diagnosis/histopathology
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Severe acute kidney injury as a complication of collagenous colitis
Severe acute kidney injury as a complication of collagenous colitis. Int J Colorectal Dis. 2016 Jun;31(6):1247-8. doi: 10.1007/s00384-015-2449-6. Epub 2015 Nov ...Missing: microscopic | Show results with:microscopic
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Severe acute kidney injury as a complication of collagenous colitis
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[57]
Microscopic colitis is a risk factor for low bone density
Jun 15, 2023 · Chronic watery diarrhea in MC may lead to calcium and vitamin D loss, which ultimately can manifest in osteoporosis or osteoporosis-related ...
[58]
Microscopic colitis is a risk factor for low bone density - Sage Journals
Jun 15, 2023 · Our data demonstrate that MC is associated with a twofold risk for LBD. Based on our findings, we suggest screening patients for bone mineral density upon ...
[59]
Microscopic Colitis: An Underestimated Disease of Growing ... - MDPI
In more severe forms of microscopic colitis, electrolyte imbalance and dehydration may occur, necessitating subsequent hospitalization. The disease is ...Missing: hypokalemia vitamin B12 deficiency megacolon
[60]
Microscopic colitis in patients with mild duodenal damage - NIH
CD presents often signs and symptoms such as chronic diarrhea, bloating, abdominal pain and malabsorption[4]. However, in a substantial number of cases, CD ...Abstract · Discussion · Comments<|control11|><|separator|>
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Microscopic colitis: Struggling with an invisible, disabling disease
The most common symptoms are watery, nonbloody diarrhoea, severe urgency, faecal incontinence, abdominal pain and weight loss (Hjortswang et al., 2009). As ...
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Collagenous colitis as a possible cause of toxic megacolon - PubMed
Collagenous colitis is a microscopic colitis characterized by normal appearing colonic mucosa on endoscopy. It is regarded as a clinically benign disease ...
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Cancer risk in microscopic colitis: a retrospective cohort study - NIH
Jan 5, 2019 · Conclusions. In conclusion, we demonstrate that microscopic colitis is not associated with increase in risk of colonic or extra-colonic cancers.
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Microscopic Colitis Is Associated With a Reduced Risk of Colorectal ...
Dec 30, 2021 · The present systematic review indicated that patients with MC may be associated with a lower risk of colorectal adenoma or cancer.Abstract · Introduction · Methods · Results
[65]
Microscopic Colitis Is Associated With a Reduced Risk of Colorectal ...
Oct 3, 2022 · Conclusions: The present systematic review indicated that patients with MC may be associated with a lower risk of colorectal adenoma or cancer.
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Microscopic Colitis: What Is It, and What Are the Treatment Options?
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Factors associated with long-term clinical outcome in microscopic ...
The incidence of microscopic colitis has increased over the last two decades. In a North American study in 2001, the prevalence of ...
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A nationwide cohort study of the incidence of microscopic colitis in ...
Epidemiological studies of microscopic colitis have shown varying but increasing incidence rates. Aim: To assess the incidence of microscopic colitis in Sweden.Missing: geographic variations Asia
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Low prevalence of 'classical' microscopic colitis but evidence of ...
May 8, 2013 · 'Classical' microscopic colitis is uncommon in Malaysian patients with IBS-D but a significant number of adults showed evidence of microscopic ...
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Microscopic Colitis (Lymphocytic and Collagenous), Eosinophilic ...
MC appears to be a disease of the older female population. The mean age for CC was 60 and for LC was 63. The proportion of women is slightly higher for CC ...Missing: demographics | Show results with:demographics
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Microscopic Colitis in a Young Male: Unveiling the Rarity - PMC - NIH
Jan 4, 2024 · MC is rarely seen under 30 years of age and is less common in males. Our case highlights an exceedingly uncommon clinical setting as it involves a young male.
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Identification of Menopausal and Reproductive Risk Factors for ... - NIH
Aug 23, 2018 · Microscopic colitis is a chronic inflammatory disorder of the colon primarily affecting postmenopausal women.
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Incidence and Prevalence of Microscopic Colitis Between ... - PubMed
Dec 2, 2020 · 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 ...
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Genome-Wide Association Study of Microscopic Colitis in the UK ...
May 24, 2019 · Microscopic colitis patients had a higher genetic risk for all three tests, but only CD [p = 0.035] and IBD [p = 0.019] were significant at the ...Missing: family history
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Smoking and Risk of Microscopic Colitis: A Systematic ... - PubMed
Mar 14, 2019 · Relative to never-smokers, current smokers had significantly increased odds of microscopic colitis, with a pooled OR of 2.99 (95% CI, 2.15-4.15; ...
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Risk Factors for Microscopic Colitis: A Systematic Review and Meta ...
Jul 17, 2025 · Microscopic colitis (MC) has an incidence of approximately 11.4 cases per 100.000 person‐years [1]. MC is a chronic inflammation of the large ...
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Alcohol Consumption is Associated With An Increased Risk of ... - NIH
Sep 2, 2021 · In summary, we found that alcohol consumption was associated with increased risk of MC in a large, prospective cohort study of female health ...
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Breast milk is rich in nutrients and immunological factors capable of protecting infants against various immunological diseases and disorders.Missing: microscopic | Show results with:microscopic
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'Collagenous colitis' with watery diarrhoea--a new entity? - PubMed
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Lymphocytic ("microscopic") colitis: a comparative histopathologic ...
Lymphocytic colitis, previously termed "microscopic colitis", is a clinicopathologic syndrome of watery diarrhea, grossly normal colonoscopy, and mucosal ...Missing: 1985 | Show results with:1985
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Microscopic Colitis – A Missed Diagnosis in Diarrhea-Predominant ...
Clinical presentation in microscopic colitis (MC) is similar in many cases to that of diarrhea-predominent irritable bowel syndrome (IBS-D).
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Human Leukocyte Antigen Signatures as Pathophysiological ...
Mar 1, 2024 · Methods: We conducted a genome-wide association study [GWAS] meta-analysis in 1498 CC, 373 LC patients, and 13 487 controls from Europe and ...Missing: 2020-2025 | Show results with:2020-2025
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Association of distinct microbial and metabolic signatures with ...
May 23, 2025 · Here, we show distinct shifts in gut microbiome and metabolome in MC that can inform the development of non-invasive biomarkers and novel therapeutics.
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Faecal Microbiota Transplantation for Microscopic Colitis
Faecal Microbiota Transplantation for Microscopic Colitis. ClinicalTrials.gov ID NCT05998174. Sponsor Hvidovre University Hospital. Information provided by ...
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Biologicals and JAK inhibitors hold promise in microscopic colitis
Apr 18, 2024 · Biologic agents and small molecules appeared to be effective options in patients with microscopic colitis (MC) who were mostly budesonide-refractory or ...Missing: II | Show results with:II
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Risk Factors for Microscopic Colitis Identified: NSAIDs, Statins, PPIs ...
Aug 29, 2025 · Individuals who received treatment with NSAIDs and statins had an increased risk for microscopic colitis.Missing: demographics | Show results with:demographics
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Rediscovering histology – the application of artificial intelligence in ...
Mar 17, 2025 · Integrating artificial intelligence (AI) into histologic disease assessment is transforming the management of inflammatory bowel disease (IBD).
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SARS-CoV-2 as a potential trigger for microscopic colitis in a young ...
Aug 15, 2024 · This case highlights the potential role of SARS-CoV-2 in triggering lymphocytic colitis, emphasizing the need for further research and vigilance.