Microscopic colitis is an inflammatory disease of the bowel. It is characterised by watery diarrhoea, usually accompanied by urgency
and problems with bowel control. People affected often need to identify where toilets are when they leave the house, to avoid accidents. The condition can also cause abdominal pain, tiredness, dehydration and weight loss. Symptoms can be bad and lead to a substantial loss of quality of life.

Microscopic colitis can develop at any time but it is more common in middle-age, with those affected often diagnosed between the ages of 50 and 60. It also occurs more frequently in women.


It is not yet clear what causes microscopic colitis. It is possible that the inflammation might be caused by the body’s immune system overreacting to bacteria that live normally in the bowel or responding to an infection from toxic bacteria or some viruses. Other risk factors, such as bile acid malabsorption and some medications, are currently being considered. Examples of medications that have been linked to microscopic colitis include non-steroidal anti-inflammatory drugs (such as ibuprofen and aspirin); protein pump inhibitors (such as lansoprazole and omeprazole); some diabetic medications (acarbose); some antidepressants (sertraline); and some anticoagulant medications (ticlopidine).

Micrograph of collagenous colitis, a type of microscopic colitis.


The condition is thought to be under-diagnosed, which means people with these symptoms might actually have microscopic colitis that has been mistakenly identified for another condition (most often misdiagnosed as IBS or diverticular disease). This is partly due to low awareness among some health professionals but also partly because of how the condition appears. Unlike other inflammatory bowel diseases, like Crohn’s disease or ulcerative colitis, the lining of the bowel appears normal when investigated with a colonoscope (a flexible tube with a camera at the end used to examine the inside of the bowel). It is only if a biopsy (a small tissue sample) of the bowel is taken and examined under the microscope that the inflammation can be seen.

Guts UK is keen to ensure those affected become aware of the condition, so they can discuss it with the health professionals looking after them. This is true both for those who have not been diagnosed and also for those not fully settled on their current treatment. Diagnosis can be easier if more symptoms and signs are considered, in addition to the presence of watery diarrhoea. People who have microscopic colitis sometimes have other diseases that affect the immune system such as some thyroid problems, coeliac disease, rheumatoid arthritis, psoriasis and diabetes. Even if they are not directly affected by an autoimmune disease, a close blood relative might be affected. Anaemia is also sometimes present in people with microscopic colitis and can also provide clues that can aid a quicker diagnosis.


The really good news is that microscopic colitis can be treated. The correct diagnosis and treatment can make a huge and dramatic difference to a person’s quality of life. We don’t want anyone suffering in silence so Guts UK wants to raise awareness of this easily overlooked condition and put the patient in control.

Microscopic colitis can be treated with small changes to the diet, a course of steroids or with symptom-relieving medicines. This strengthens the case for better diagnosis of this condition, which Guts UK hopes will happen through raising awareness among the public and health professionals.



For more information on Microscopic Colitis click here. (Courtesy of Crohns & Colitis UK)


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