Microscopic colitis (MC) is an inflammation of the colon that causes chronic, non-bloody watery diarrhoea.
Patients with MC can experience abdominal pain, faecal incontinence and weight loss; symptoms that heavily impair their quality of life. Association of MC with autoimmune diseases, such as rheumatism, thyroid disease, diabetes or coeliac disease is not uncommon.
The colonic mucosa of patients with MC appears normal on visual inspection by colonoscopy. For this reason, patients are often misdiagnosed with IBS. Biopsies from the whole colon are often deemed necessary for the right diagnosis and only histological examinations can reveal if the diarrhoea is caused by lymphocytic (LC) or collagenous colitis (CC). LC and CC show similar signs and symptoms with the difference that LC causes an increase in the number of lymphocytes whilst CC is characterised by the thickening of the collagen band in the mucosa of the colon.
For active MC, short-term budesonide drugs are prescribed as a first-line therapy.1
1. References: EMCG Guidelines: Munch et al. J Crohns Colitis 2012; 6(9):932-45. Epub 2012 Jun 15.