Microscopic colitis is a disease of the large intestine. It is a common cause of chronic, watery diarrhea. The disease, the exact cause of which is still unknown, occurs most frequently in people over the age of sixty. Women are affected up to three times more often than men. Certain therapy options have been discussed. These therapy ideas include worm eggs, which might cause a little aversion upon first hearing it. Microscopic colitis is divided up into collagenous colitis andlymphocytic colitis. It occurs just as frequently as the inflammatory bowel diseases Crohn's disease and ulcerative colitis.
What is microscopic colitis?
Colitis is an inflammation of the colon, i.e. large intestine. Such inflammation is usually accompanied by pronounced reddening and injuries to the lining of the intestine. Such changes are visible in a colonoscopy.
Microscopic colitis got its name because it occurs without the changes typical of inflammation. Instead, the changes in this disease can only be seen under a microscope.
What causes microscopic colitis?
Doctors are unsure of the exact causes of microscopic colitis. The following are discussed as triggers:
- Allergic causes
- Autoimmune causes
- Other causes
Allergic causes
There is evidence that allergens in the gastrointestinal tract are responsible for the formation of microscopic colitis. Various studies have shown a connection between the introduction of various allergy-causing substances and the appearance of microscopic intestinal inflammation.
Autoimmune causes
Another theory says that the immune system is responsible for the appearance of colitis. Through dysregulation in the body's own immune system it can happen that the immune system recognizes parts of the intestinal mucosa as “foreign” and attacks them. This explains the inflammation in the intestine without an obvious cause.
Other causes
Other causes of microscopic colitis have been discussed among medical professionals. These include side effects of various medications, effects of bacterial infections of the intestine and some metabolic disorders.
What types of microscopic colitis are there?
Microscopic colitis occurs in two different forms:
- Collagen colitis: In this variant of the disease, there is an enlargement of a band of connective tissue that lies under the upper cells of the intestinal mucosa. Since this band consists mainly of the connective tissue protein collagen, it is called collagenous colitis
- Lymphocytic colitis: Lymphocytes are cells of the immune system. Some of these cells are located in the lining of the intestine to help ward off potentially harmful foreign bodies (pathogens). With lymphocytic colitis there is a proliferation of these cells in the intestinal mucosa and thereby increased inflammatory activity
What are the symptoms of microscopic colitis?
The main symptom of microscopic bowel inflammation is diarrhea. The watery diarrhea is generally chronic. Unwanted bowel movements at night are also common. Many patients also experience irregular, strong stomach pain. Many sufferers also experience weight loss, which is usually limited to a few kilograms. In rare cases, there can be a loss of ten to fifteen kilograms of body weight.
Fever, vomiting, or bloody stools, which are common in other intestinal diseases and inflammations, are rarely associated with microscopic colitis. If they occur in addition to the symptoms of microscopic colitis, another intestinal disease should be considered.
Some patients with microscopic colitis can also have autoimmune diseases. The most common include autoimmune joint pain, rheumatoid arthritis and autoimmune thyroid disorders.
How does the doctor diagnose microscopic colitis?
If watery diarrhea occurs in a patient over a period of four weeks, the doctor should carry out a colonoscopy. As part of this examination, tissue samples from several sections of the intestine are taken, i.e. so-called serial biopsies. These biopsies can then be examined under a microscope and the diagnosis of microscopic colitis made.
How is microscopic colitis treated?
Since the exact cause of microscopic colitis is not yet known, the therapy is mainly limited to treatment of symptoms caused by this condition.
Pain reliever for the treatment of microscopic colitis
A first step is to stop taking medications that are associated with the appearance of microscopic colitis. The most important of these drugs are so-called non-steroidal anti-inflammatory drugs (NSAIDs). This group of drugs includes, among others paracetamol and ibuprofen, Refraining from taking NSAIDs can alleviate the symptoms of microscopic colitis. Restricting coffee consumption has also shown positive effects in many patients.
Diarrhea medication for the treatment of microscopic colitis
In the case of acute, severe diarrhea, short-term therapy with loperamide can help relieve the discomfort. This medication inhibits the intestinal movement (peristalsis) and can thus help to reduce the frequency of stool. Activated carbon can also help relieve the diarrhea.
Anti-inflammatory medications to treat microscopic colitis
If the symptoms persist, therapy with so-called bismuth subsalicylate can be tried. This substance works as an anti-inflammatory and can help alleviate an upset gastrointestinal tract.
The inflammation itself is mainly treated with the help of so-called corticosteroids, which includes cortisol. This group of drugs affects the human immune system and inhibits its excessive activation. This can reduce the inflammatory activity with microscopic colitis. The corticosteroids include many different drugs. Budesonide, a drug from this group, is recommended for the treatment of microscopic colitis.
Worm eggs for the therapy of microscopic colitis
A new approach that is currently still being researched in studies is probiotic therapy with worm eggs. The eggs of certain worms (helminths) are introduced into the intestine. They are said to help balance the natural intestinal flora and thus reduce inflammatory activity. It remains to be seen whether such therapy is effective in humans.
Does diet affect microscopic colitis?
In general, the effects of changing your diet with microscopic colitis are controversial. Refraining from coffee has proven to help alleviate the symptoms. Other foods that have a significant influence on the clinical picture are, however, not known. Since allergens are discussed as a possible cause of the disease, the omission of certain foods could have positive effects. Which foods these are varies from patient to patient. It is advisable to keep a food diary for a few weeks and record the body's reactions to various foods. In this way, individual factors can be determined that influence the course of the intestinal inflammation.
What is the prognosis of microscopic colitis?
Approximately 60 percent of patients respond to therapy for microscopic colitis. For some people, giving up NSAIDs and coffee can help to greatly alleviate the disease. However, relapses often happen even with successful therapy. These usually occur several years after the initial treatment and improvement of the symptoms. It is therefore recommended that a so-called “maintenance treatment” be undertaken, in which the medication continues to be administered six to twelve months after the symptoms have improved.
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