What is Microscopic Colitis?
IBD is a group of conditions that cause inflammation in either the small or large intestine. Microscopic Colitis is an inflammation of the large intestine (colon) that causes persistent watery diarrhoea.
There are two main forms:
- Collagenous Colitis (CC) – a thick layer of protein (collagen) develops in colon tissue
- Lymphocytic Colitis (LC) – white blood cells (lymphocytes) increase in colon tissue
However, with Incomplete Microscopic Colitis, there are mixed features of collagenous and lymphocytic colitis.
The disorder gets its name from the fact that it’s necessary to examine colon tissue under a microscope to identify it.
The severity, frequency, and duration of symptoms vary. People with this condition can experience flare-ups when they experience frequent symptoms, but also periods of remission.
Equally some people may have painful, disabling symptoms, others only experience mild discomfort. And, while many people experience flare-ups that last a few days or weeks, other people have symptoms that last for months to years.
Common symptoms include:
- abdominal cramping
- pain dehydration
Women, people over the age of 50 and people who have an autoimmune disease (the immune system attacks the body) are more likely to have microscopic colitis.
An estimated 75 percent of cases develop in people 50 years of age or older, though some cases in children have been reported.
Microscopic colitis may have several different causes, studies suggest there is not one single cause, but a combination of several, setting off an inflammatory response. Primary contributory factors include:
- Certain autoimmune diseases, including celiac disease, thyroid diseases, rheumatoid arthritis and psoriasis
- Medications, including non-steroid anti-inflammatory drugs like aspirin and ibuprofen
- Antacid and heartburn drugs; antidepressants; and certain drugs for treatment of cancer or heart disease
MedicationsIf signs and symptoms persist, your doctor may recommend:
- Anti-diarrheal medications such as loperamide (Imodium) or bismuth subsalicylate (Pepto-Bismol)
- Steroids such as budesonide
- Medications that block bile acids (which can contribute to diarrhoea) such as cholestyramine/aspartame or cholestyramine (Prevalite), or colestipol (Colestid)
- Anti-inflammatory medications such as mesalamine to help control colon inflammation
- Medications that suppress the immune system to help reduce inflammation in the colon, such as mercaptopurine (Purinethol) and azathioprine (Azasan, Imuran)
- TNF inhibitors, such as infliximab (Remicade) and adalimumab (Humira), which can reduce inflammation by neutralizing an immune system protein known as tumour necrosis factor (TNF)
SurgeryWhen the symptoms of microscopic colitis are severe, and medications are not effective, your doctor may recommend surgery to remove all or part of your colon. Surgery is rarely needed to treat microscopic colitis.
IBS Clinics approachIBS Clinics nutritionists are fully conversant in a wide range of dietary approaches and so a typical patient may be recommended to follow a gluten free, Casein free diet.
Many research reports point out that laboratory markers and clinical symptoms of celiac disease and MC are very similar. Both celiac disease and microscopic colitis are associated with an elevated lymphocyte count in the mucosa of the intestine. With celiac disease, the lymphocytic infiltration eventually leads to villus atrophy in the small intestine. This is typically true if the patient has either a DQ2 or a DQ8 gene (Biagi et al., 2004). Note that an early stage of celiac disease, known as Marsh stage 1 enteropathy, is marked by an intraepithelial lymphocyte count greater than 30 lymphocytes per 100 enterocytes. So, both celiac disease and microscopic colitis cause identical cellular changes in the mucosa of the colon. And even though no mention of the small intestine is made in the diagnostic criteria for microscopic colitis, researchers have found that lymphocytic infiltration is frequently present in the small intestine of MC patients, and in some cases, villus damage is sufficient to justify a diagnosis of celiac disease. Even when the formal diagnostic criteria for celiac disease are not met, a significant number (over 10 %) of microscopic colitis patients show at least a Marsh 1 level of villus damage upon biopsy analysis of their small intestine (Simondi et L., 2010).
Casein (dairy) sensitivities and other commonly allergenic foods (soy, eggs, nuts)
A few people who have MC are sensitive to the primary storage proteins in other grains, such as zein (in corn), or panicin (in millet), and orzenin (in rice). Experience shows that rice is one of the least allergenic grains of the commonly available choices. That means that most (but not all) of us can use it in an elimination diet. Unfortunately, grains are not the only foods that can cause immune system reactions for some people who have MC. Most people who are sensitive to gluten are also sensitive to casein, the primary protein in all dairy products, and approximately half of them are also sensitive to soya, the primary protein in soybeans. In addition, most individuals who are sensitive to soya are also sensitive to all or most foods known as legumes, a group that includes most beans, peas and most food grade gums that are used to replace gluten in gluten-free flours. These gums include guar gum, locust bean gum and carob bean gum. In addition to the most common food sensitivities, some people who have MC are also sensitive to foods such as eggs, yeast, corn, nuts, and occasionally other foods.
If no significant improvement in symptoms is seen after several months of eliminating all known or suspected food sensitivities from the diet, then it might be time to suspect a mast cell problem, and to try some diet modifications, in order to confirm whether or not mast cells are indeed the source of the problem.
Histamine and Mast cell activation syndrome (MCAS)Unfortunately, the gastrointestinal symptoms of histamine disorders may be overlooked because they overlap the symptoms of microscopic colitis. These symptoms include, but are not limited to, headache, abdominal pain, gas, cramps, and diarrhoea.
The research is very persuasive on the activity of mast cell activation in the gut and the triggering of histamine release in response to chronic inflammation. MC is a condition characterized by chronic inflammation. A study published in 2006 showed that 70 % of patients with what was described as “chronic intractable diarrhoea”, had an elevated mast cell count that qualified for a diagnosis of mastocytic enterocolitis.
OxalatesOxalates may cause problems for some people who have MC. Oxalates are known to be a problem for people who have short bowel syndrome. Short bowel syndrome (SBS) normally refers to individuals who have had significant sections of their intestines surgically removed and who have problems with diarrhoea because of the procedure. In a sense, many MC sufferers have an MC-induced version of SBS because of functional issues such as a severe malabsorption problem caused by massive inflammation. This implies that significant sections of the intestines do not function very well, even though the digestive system is still intact. With SBS, the problem can be caused by foods that have a high oxalate content, such as beets, collards, cocoa, chocolate, green beans, kale, Ovaltine, parsley, raw nuts, rhubarb, spinach, strawberries, sweet potatoes, tea, turnip greens, and some instant coffees. Note that colas also contain oxalate and should be limited to approximately 12 oz. per day with SBS. This may be the reason why experience shows that many who have MC cannot tolerate foods such as chocolate, sweet potatoes, and nuts, when there is no other logical reason why they should not be tolerated.
SalicylatesThere appears to be some research to suggest that a small subset of people with IBD may have a salicylate intolerance. Salicylates naturally occur in varying concentrations in many fruits and vegetables, and are chemically very similar to the man-made chemical, acetylsalicylic acid, a key ingredient in aspirin and other pain medications. They are also frequently found in acne and wart removal products, aspirin, many NSAIDs, and other medications, both natural and pharmaceutical products such as cosmetics, fragrances, perfumes, lotions, hair spray, gels, shampoo and conditioners, bubble baths. Some herbs are especially high in salicylates for example curry powder contains 218 mg salicylate per 100 g. Others almost as high were paprika, thyme, dill powder, garam masala, oregano, and turmeric.
LectinsLectins can be an issue for some people and so a brief trial of a low lectin diet might be helpful in determining if this is an issue.
Tests and supplements
Because intestinal issues often appear normal in microscopic colitis, a definite diagnosis of microscopic colitis requires a colon tissue biopsy. This can be taken during a colonoscopy or flexible sigmoidoscopy. In both subtypes of microscopic colitis, cells in colon tissue have a distinct appearance under the microscope, giving a definitive diagnosis.