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Microscopiccolitis: A literature review
Rev Assoc Med B ras 2016; 62(9):895-900 895
REVIEW ARTICLE
Microscopic colitis: A literature review
Ana Paula Hamer Sousa Clara1, F lávia Drago Magnago2, Juliana Neves Ferreira 2, Thais Gagno Grillo2*
1MSc in Public Policies and Local Development from Escola Superior de Ciências da Santa Casa de Misericórdia de Vitória (Emescam). Professor of Semiology and Internal Medicine at Emescam, Vitória, ES, Brazil
2MD from Emescam, Vitória, ES, Brazil
Summary
Study conducted at Escola Superior de
Ciências da Santa Casa de Misericórdia
de Vitória (Emescam), Vitória, ES, Brazil
Article received: 6/25/2015
Accepted for publication: 7/6/2015
*Correspondence:
Address: Rua Jofredo Novaes, 133,
apto. 601, bloco A
Vila Velha, ES – Brazil
Postal code: 29101-470
Microscopic colitis (MC) refers to chronic inflammation of the colon which is
characterized by histologic changes at the level of a radiologically and endoscop-
ically normal mucosa. It is a common cause of chronic non-bloody diarrhea that
occurs primarily in older individuals; however, there are few studies in the liter-
ature with strong scientific evidence compared to other inflammatory bowel dis-
eases (IBD), which limits the knowledge of physicians and pathologists. This ar-
ticle aims to review the information on MC, describing diagnostic methods and
drugs available for treatment. We conducted a search of the Pubmed database
and CAPES Portal using the keywords “microscopic colitis”, “collagenous coli-
tis”, “lymphocytic colitis”, and “review” for selection of articles published be-
tween 1996 and 2015 related to the topic. Based on the studies discussed in this
review, we conclude that MC is a relatively new gastrointestinal disorder, most
studies are incipient particularly with respect to pathophysiology and immu-
nology, and budesonide is the best documented short-term treatment. Howev-
er, further studies are needed to elucidate the best strategy for treatment in the
long term.
Keywords: microscopic colitis, collagenous colitis, lymphocytic colitis, review.
Introduction
Microscopic colitis (MC) refers to chronic inflammation
of the colon which is characterized by histologic chang-
es at the level of a radiologically and endoscopically nor-
mal mucosa. It is a common cause of chronic non-bloody
diarrhea that occurs primarily in older individuals, ac-
counting for 10 to 20% of cases.1
Collagenous colitis (CC) was described in 1976 by
Lindstrom and Freeman with clinical and histological
features similar to MC, except for the presence of a thick
band of subepithelial collagen. The term MC was used
in 1980 to describe patients with chronic watery diar-
rhea and normal findings on sigmoidoscopy and bari-
um enema but with microscopic inflammation on co-
lon biopsy. It is unclear whether these two conditions
represent separate diseases or are phenotypes of the
same disease.2
Currently, MC includes two subsets: CC, with a thick
band of subepithelial collagen, and lymphocytic colitis
(LC), without collagen thickening and with an increase
in the number of intraepithelial lymphocytes (≥ 20/100
epithelial cells).2,3
Method
The literature review was adopted for the preparation of
this article on MC. Data was collected from articles pub-
lished between 1996 and 2015 in journals indexed in the
Pubmed and CAPES Portal search engines. The keywords
used were “microscopic colitis”, “collagenous colitis”,
“lymphocytic colitis” and “review” for the selection of ar-
ticles related to the topic. The search included original
articles and literature reviews published in English. The
research was also complemented by articles referenced in
other publications already selected. The investigation was
only concluded when signs of theoretical saturation of
the research topic emerged.
Epidemiology
Several risk factors have been described for MC, the main
ones including: female, advanced age, autoimmune dis-