Clear cell colitis: A form of microscopic colitis in children

Microscopic Colitis: An Underestimated Disease of Growing Importance

The aim of this paper is to raise awareness of MC as a clinically significant condition and to highlight its under-recognition, risk factors, diagnosis, management, and complications. This paper underlines the diagnostic and therapeutic challenges associated with the often nonspecific symptoms of MC. In order to create this article, we reviewed available articles found in the PubMed database and searched for articles using the Google Scholar platform. Microscopic colitis (MC) is a chronic inflammatory bowel disease, classified into three types: lymphocytic, collagenous, and unspecified. The average age of onset of MC is around 62-65 years and the disease is more common in women than men (nine times more common). The main symptom of MC is watery diarrhoea without blood, other symptoms include defecatory urgency, faecal incontinence, abdominal pain, nocturnal bowel movements, and weight loss. Once considered a rare disease, MC is now being diagnosed with increasing frequency, but diagnosis remains difficult. To date, a number of causative factors for MC have been identified, including smoking, alcohol consumption, medications (including NSAIDs, PPIs, SSRIs, and ICPIs), genetic factors, autoimmune diseases, bile acid malabsorption, obesity, appendicitis, and intestinal dysbiosis. It may be difficult to recognize and should be differentiated from inflammatory bowel diseases (Crohn's disease and ulcerative colitis), irritable bowel syndrome (IBS), coeliac disease, infectious bowel disease, and others. Diagnosis involves biopsy at colonoscopy and histopathological evaluation of the samples. Treatment consists of budesonide oral (the gold standard) or enema. Alternatives include bile acid sequestrants (cholestyramine, colesevelam, and colestipol), biologics (infliximab, adalimumab, and vedolizumab), thiopurines, methotrexate, and rarely, surgery.

Microscopic colitis in older adults: impact, diagnosis, and management

Microscopic colitis (comprising lymphocytic and collagenous colitis, albeit an incomplete variant is gaining recognition as well) is a chronic, immune-mediated inflammatory state of the lower gastrointestinal tract (colon). The diagnosis requires diagnostic colonoscopy with characteristic histopathological findings. They have a propensity to present in senior populations (above 60 years of age), particularly women - who are approximately 2.5-3 times more likely to develop microscopic colitis. Preexisting other immune-inflammatory diseases are also shown to predispose patients for the development of microscopic colitis. The classic presentation is profuse watery diarrhea, often during the night or early morning hours. Fecal incontinence and abdominal pain are frequent as well. Thus, the disease impacts patients' quality of life and well-being. The first described cases date back to the seventies and eighties of the twentieth century, thereby they can be considered fairly recently discovered disease states. Our understanding of the disease and its pathophysiology is still incomplete. Although there is a lack of unified recommendation for treatment, most clinicians prefer the use of budesonide, and most published guidelines regard this locally acting glucocorticoid as the therapy of choice. In our article, we aimed for a brief, noncomprehensive overview of the clinical significance, diagnosis, and management of microscopic colitis.

Microscopic colitis: controversies in clinical symptoms and autoimmune comorbidities

BACKGROUND

Microscopic colitides are chronic immune-inflammatory bowel diseases. The typical presentation is chronic, watery diarrhoea. Inflammation mostly cannot be visualized via macroscopic inspection. The diagnosis thus requires histologic sampling. The clinical picture can vary. New investigations can prove valuable in setting up recommendations.

PATIENTS

A total of 103 patients with microscopic colitis (MC) [28 lymphocytic colitis (LC) 27.2%, 75 collagenous colitis (CC) 72.8%] in the Clinical Centre of the University of Debrecen (tertiary care centre) were included, diagnosed between 1993 and 2020. We aimed for a retrospective analysis characterizing Hungarian MC patients. We sought to compare two subgroups of patients (with either LC or CC). Our investigation focussed on dominant alteration of stool habits, autoimmune and allergic comorbidities. Autoimmune diseases were diagnosed in 39% (40) of the patients, allergic diseases in 26.2% (27) of patients and 22.2% of tested patients had alimentary hypersensitivity to certain foods (18 cases out of 81 tested).

RESULTS

Age of diagnosis was younger in LC (44.5 years, SD: 5.3 vs. 51.9 years, SD: 12.8, difference= 7.4 years p = .0151). Autoimmune diseases were equally frequent in the two groups (LC: 10 patients 36%, CC: 30 patients, 40%, difference: 4%, p = .7124). Food-linked hypersensitivities were more common in CC (LC: 1 patient, CC: 17 patients). Difference in allergic diseases (asthma, rhinitis, urticaria) did not differ between groups (LC: 6 patients, 21%; CC: 21 patients, 28%, difference: 7% p = .4739). One-third of the patients did not complain about chronic diarrhoea. These patients had chronic constipation as the main symptom (34 patients, 33%).

CONCLUSION

Pre-existing autoimmune and allergic diseases were common in patients with MC. Chronic watery diarrhoea is not experienced in many cases. The absence of certain symptoms should not be used to rule out the condition.

The association between smoking and both types of microscopic colitis: A systematic review and meta-analysis

BACKGROUND AND STUDY AIMS

It has been suggested that smoking may be associated with microscopic colitis (MC) in some studies; however, there are conflicting results in the current literature with many of these studies having significant limitations. Our study aims to offer a meta-analysis evaluating the association between MC, including both its subtypes, and smoking.

PATIENTS AND METHODS

A systemic review was conducted in PUBMED, Embase, PubMed Central, and ScienceDirect databases from inception through December 2019. Effect estimates from the individual studies were extracted and combined using the random effect, generic inverse variance method of DerSimonian and Laird and a pooled odds ratio (OR) was calculated. Forest plots were generated, and publication bias was assessed for using conventional techniques.

RESULTS

Eight observation studies with a total of 1461 patients with MC were included in this study, 383 of whom were active smokers (26.2%). Current smoking was significantly associated with MC (OR 3.58, 95% CI, 2.51-5.11), lymphocytic colitis (LC) (OR 3.64, 95% CI, 2.46-5.38), and collagenous colitis (CC) (OR 4.43, 95% CI, 2.68-7.32). Gender-specific subgroup analysis showed a significant association with smoking was found for CC in men (OR 4.53, 95% CI, 1.59-12.85), CC in women (OR 3.27, 95% CI, 2.35-4.54), LC in women (OR 2.27, 95% CI, 1.27-4.06) and MC in women (OR 2.93, 95% CI, 2.09-4.10). We found no publication bias as assessed by the funnel plots and Egger's regression asymmetry test.

CONCLUSION

Our meta-analysis found a statistically significant association between smoking and both subtypes of MC.

Microscopic colitis in children with chronic diarrhea

OBJECTIVE

The aim of the present study was to study microscopic colitis (MC) in children with special reference to its role in chronic diarrhea and changes in mucosal biopsies.

METHODS

A total of 100 consecutive children ages 3 to 12 years, with nonbloody diarrhea (passage of ≥3 loose stools per day) of >12 weeks' duration were screened and 26 were enrolled in the study in which no specific etiology could be found and colonoscopy did not reveal any mucosal abnormality. Colonic biopsies were evaluated for the presence of lymphocytic colitis or collagenous colitis and those with the characteristic changes were defined to have MC (group A). Colonic biopsies from patients with MC were compared with biopsies from patients with chronic diarrhea but no evidence of MC (group B). One hundred children ages 3 to 12 years with bleeding per rectum were screened and colonic biopsies from 45 patients (group C) who had colonic mucosal changes but no vascular or polyp lesion were compared with patients with MC.

RESULTS

Of the 26 patients with chronic diarrhea, MC was found in 5 (3 lymphocytic colitis and 2 collagenous colitis). Significantly higher polymorphonuclear infiltration was seen in group A as compared with group B (13.8 [5.4-20.6] vs 7.2 [0-19.6]; P = 0.03) or group C (13.8 [5.4-20.6] vs 4 [0-13.4]; P = 0.007). Intraepithelial lymphocytes (12 [4-32] vs 4 [0-24]; P = 0.008) and basement membrane thickening (3.5 [2.9-10.6] vs 2.5 [1.6-5.86]; P = 0.008) were also significantly higher in group A as compared with group C.

CONCLUSIONS

MC was found to be present in children with nonbloody chronic diarrhea in children. Further multicentric studies may provide adequate data on its prevalence.

Diagnosis and therapy of microscopic colitis with presence of foamy macrophages in children

We discuss the diagnosis of and efficacy 5-amino-2-hydroxybenzoic acid (5-ASA), Saccharomyces boulardii, or magnesium in therapy of microscopic colitis with presence of foamy macrophages. A basis for diagnosis and inclusion to the analysed group was presence of characteristic foamy macrophages in histopathological examination of hematoxylin and eosin-stained specimens collected from the large intestine, reviewed under ×200 or ×320 magnification. No statistically significant improvement was found following the use of 5-amino-2-dihydroxybenzoic acid in therapy of the disease. The use of Saccharomyces boulardii was associated with statistically significant improvement in clinical, endoscopic, and histopathological condition. Use of magnesium caused a histological, statistically significant improvement but failed to have any effect on the clinical and endoscopic presentation. In the group of children in whom no therapeutic intervention was provided, a statistically significant spontaneous clinical improvement was observed, but no statistically significant changes in endoscopic and microscopic condition were found.

Microscopic colitis in children

BACKGROUND

Microscopic colitis typically presents with chronic watery nonbloody diarrhea with normal endoscopy findings but abnormal inflammatory histopathological findings. As it is mainly a condition of the elderly, pediatric data is scarce.

AIMS

To describe and characterize children with microscopic colitis.

METHODS

The pathology database at the University of Alberta Hospital together with the pediatric inflammatory bowel disease database at the Stollery Children's Hospital were both searched from September 1996 to May 2008. Charts of all children under the age of 17 years who fulfilled the diagnostic criteria of microscopic colitis were examined.

RESULTS

Eleven children (four girls, mean age at diagnosis 11.2 years, +/- 4.4 years) fulfilled the inclusion criteria. The patients were followed up for a mean of 24.8 months (standard deviation, SD 15.2 months). Two patients were on proton pump inhibitors, two had stool organisms, and two had immunodeficiency. All patients had normal endoscopy and colonoscopy on visualization. Five patients were diagnosed with lymphocytic colitis and the rest had nonspecific/eosinophilic microscopic colitis. The majority of children responded to mesalazine. One patient with immunodeficiency was difficult to manage.

CONCLUSIONS

Microscopic colitis is rare in children. Microscopic eosinophilic colitis is an underdescribed variant of microscopic colitis. The majority of children with microscopic colitis respond well to aminosalicylic acid (5-ASA) medications. Microscopic colitis associated with immunodeficiency can be very challenging to manage. Large multicenter pediatric trials with long-term follow-up are needed to allow investigators to have a better understanding of this rare condition in children.

Lymphocytic, collagenous and other microscopic colitides: pathology and the relationship with idiopathic inflammatory bowel diseases

SUMMARY

Collagenous colitis and lymphocytic colitis are the two major conditions characterized by chronic watery diarrhoea, without endoscopic or radiological lesions, but with histological abnormalities and therefore considered as "microscopic colitis". The histology of colonic biopsies shows inflammation of the mucosa, and either thickening of the subepithelial collagen band or an increase of lymphocytes in the surface epithelium. Different variant forms have been reported under separate names. These are probably not specific entities. The incidence of microscopic colitis is slightly less than the incidence of chronic idiopathic inflammatory bowel diseases (IBD). Microscopic colitis and IBD are clearly different entities. The relation between both entities is weak but double. Biopsy samples from patients with IBD may mimic the features of lymphocytic or collagenous colitis, both in the initial onset and during follow-up. In the large majority of these cases, endoscopy shows or has shown mucosal lesions. In rare cases, however, a double diagnosis was made. Certain patients, usually of older age, presented first with a microscopic, usually collagenous colitis and developed subsequently genuine ulcerative colitis.