Chronic watery diarrhea; Microscopic colitis
Collagenous colitis (CC) is defined as a chronic nondistorting colitis with the deposition of characteristic thick collagen band immediately beneath the surface epithelium. This layer has an irregular, jagged lower edge and consists of collagen fibers, inflammatory cells, and capillaries. The average collagen width has been reported as 10–20 μm, compared with the normal basement membrane width of up to 3 μm. Patients with CC generally suffer from chronic watery diarrhea. Colonoscopy is usually normal or near normal.
The reported incidence is between 1 and 2 in 100,000.
Primarily affects middle-aged or older adults.
There is slight female predominance over males as 1.8:1.
CC involves the entire colon in a patchy fashion. In some cases there may be rectal or left colonic sparing.
Most patients with CC require anti-inflammatory therapy with either steroids or 5-ASA compounds.
References and Further Reading
- Widgren, S., Jlidi, R., & Cox, J. N. (1988). Collagenous colitis: Histologic morphometric immunohistochemical and ultrastructural studies. Report of 21 cases. VirchowsArchiv Anatomy, 413, 287–296.Google Scholar
- Langner C, Aust D, Ensari A, Villanacci V, Becheanu G, Miehlke S, Geboes K, Münch A. (2015). Working Group of Digestive Diseases of the European Society of Pathology (ESP) and the European Microscopic Colitis Group (EMCG). Histology of microscopic colitis-review with a practical approach for pathologists. Histopathology, 66(5), 613–626.Google Scholar