What is Collagenous and Lymphocytic Colitis (Microscopic Colitis)?
Microscopic colitis is a common reason for long-term watery diarrhea, especially in older people. There are two types of this condition based on the results from tissue sample tests: collagenous colitis and lymphocytic colitis. Both types share very similar symptoms where patients usually experience chronic watery diarrhea without any blood.
These two types of microscopic colitis are differentiated by their unique changes seen under microscopic examination. Because of the symptoms, medical professionals often evaluate patients for other bowel inflammation diseases such as Crohn’s disease and ulcerative colitis. The number of microscopic colitis cases has been rising in northern Europe and northern North America, particularly among females.
What Causes Collagenous and Lymphocytic Colitis (Microscopic Colitis)?
The exact causes of microscopic colitis, a condition which involves inflammation of the colon, aren’t fully understood, but it’s believed that factors like certain medications, smoking, and even genetics could play a role.
Some medications have been linked to microscopic colitis or might make its symptoms worse. The strongest links have been found with medications like nonsteroidal anti-inflammatory drugs (NSAIDs). Other drugs like proton pump inhibitors (a type of heartburn medication), especially lansoprazole, cholesterol-lowering medicines known as statins, antidepressants known as selective serotonin reuptake inhibitors, and pembrolizumab, an immunotherapy drug used to treat cancer, have also been linked to this condition.
Smoking is also believed to contribute to microscopic colitis. It’s been found that people who smoke are more likely to develop the condition, and also tend to develop it earlier, sometimes by as much as ten years, compared to those who don’t smoke.
Another possible link has been made with celiac disease, an autoimmune disorder that primarily affects the digestive tract. There are similarities between the two conditions, and both have been associated with a particular genetic marker called the HLA-DR3-DQ2 haplotype. The inflammation process is also similar in both conditions.
Risk Factors and Frequency for Collagenous and Lymphocytic Colitis (Microscopic Colitis)
Collagenous colitis and lymphocytic colitis are medical conditions that occur in certain rates. Particularly, the rate of collagenous colitis is between 2.0 to 10.8 per 100,000 individuals, while lymphocytic colitis occurs between 2.3 to 16 per 100,000 individuals. These conditions are more common in northern Europe and northern North America. Generally, most patients are diagnosed around the age of 65, however, about 25% are diagnosed before 45. It is possible for children to have these conditions, but it’s rare. Both conditions are more common in females.
Furthermore, there’s a connection between these colitis types and several other diseases with autoimmune characteristics. Specifically, people with collagenous colitis also tend to have other autoimmune diseases more often than those with lymphocytic colitis. There have been unusual cases where microscopic colitis and inflammatory bowel disease, usually ulcerative colitis, occur together. There are even reports of people having both collagenous and lymphocytic colitis at the same time.
- The occurrence rate of collagenous colitis is between 2.0 to 10.8 per 100,000 individuals.
- The occurrence rate of lymphocytic colitis is between 2.3 to 16 per 100,000 individuals.
- These conditions are more common in northern Europe and northern North America.
- Most people are diagnosed around the age of 65, however, around 25% are diagnosed before the age of 45.
- Collagenous colitis and lymphocytic colitis can occur in children, but it is rare.
- Both conditions are more common in females. The female-to-male ratio is 3.0 for collagenous colitis and 1.9 for lymphocytic colitis.
- People with collagenous colitis also tend to have other autoimmune diseases more often than those with lymphocytic colitis.
- Rare cases have been reported where a person has microscopic colitis and inflammatory bowel disease, usually ulcerative colitis, at the same time.
- There have been reports of people having both types of colitis together.
Signs and Symptoms of Collagenous and Lymphocytic Colitis (Microscopic Colitis)
Microscopic colitis is a condition often found in middle-aged or older females, but it can also affect anyone at any time in their life. Those with this condition usually experience long-term, non-bloody, watery diarrhea. This means they have at least 3 loose or watery bowel movements per day for over 4 weeks. The number of these bowel movements can range between 4 to 9 per day, but in severe cases, it can increase to 15 or more.
Other symptoms can include:
- A sensation of needing to have a bowel movement urgently
- Inability to control bowel movements
- Awakening in the middle of the night due to needing a bowel movement
- Abdominal discomfort or pain
- Joint pain
- Inflammation of the eyes
In general, microscopic colitis comprises two types: collagenous and lymphocytic. Collagenous colitis is often associated with more severe inflammation of the bowel, while lymphocytic colitis tends to develop earlier in life.
Testing for Collagenous and Lymphocytic Colitis (Microscopic Colitis)
When it comes to microscopic colitis, blood test results don’t usually give specific guidance towards its diagnosis. About half of the patients may show higher than normal levels of erythrocyte sedimentation rate, mild anemia, and some autoimmune markers. These could include rheumatoid factor and antibodies against nuclear, mitochondrial, and thyroid components. There are other signs, such as elevated levels of certain proteins and enzymes in the stool, but these haven’t been widely accepted or validated.
Sometimes, a patient might have a form of diarrhea that leads to protein loss, marked by low albumin levels in the blood. Therefore, testing for albumin levels could be useful in such cases.
Stool tests are an essential part of the diagnostic evaluation. These include tests looking for harmful bacteria such as Clostridium difficile, Escherichia coli, and Giardia among others. Another test pertains to Celiac disease; this involves checking for an antibody (tissue transglutaminase IgA antibody) linked to gluten intolerance. However, most of these stool tests usually turn out negative, indicating the need for further evaluation.
The next step in diagnosing microscopic colitis is endoscopy with mucosal biopsies. A colonoscopy, in particular, is usually the preferred method and can involve taking tissue samples from different parts of the colon. Despite the presence of inflammation, the colon often appears normal during endoscopy, although some patients may show signs such as swelling, redness, fragile tissue or even lesions and scarring. The definitive diagnosis of microscopic colitis is made based on biopsy and microscopic examination of the collected tissue samples.
Treatment Options for Collagenous and Lymphocytic Colitis (Microscopic Colitis)
The aim of treating digestive issues is to reduce the symptoms to less than three bowel movements per day without any watery discharge. This helps to enhance patients’ quality of life. The first step is to stop any potential causes of the symptoms, which may include certain drugs like nonsteroidal anti-inflammatory ones and habits like smoking.
Patients usually start their treatment with antidiarrheal drugs such as loperamide. Alone, these medicines could be enough to manage symptoms, but other drugs may also be needed. During this medication period, it’s crucial to check for any potential infections as these drugs could intensify symptoms of certain infections like C. difficile. If the patient is still having three or more bowel movements per day with at least one watery discharge, adding a drug such as budesonide is advised. This medication typically requires a 6 to 8-week treatment period for complete resolution. After that, the dosage needs to be gradually decreased. Another drug choice could be prednisone but recent studies indicate that budesonide is more effective.
If patients continue experiencing symptoms despite the above treatment, other drugs might be required. Cholestyramine, taken four times per day, can help until diarrhea is resolved. This medication is a bile acid-binding resin used specifically for diarrhea that comes with bile acid malabsorption. Should the diarrhea persist for more than two weeks, bismuth subsalicylate could be taken three times per day.
Sometimes, patients may not respond to the above treatments. It’s worth noting that 10%-20% of patients fail to respond to such treatments. If this happens, other treatments like antitumor drugs and immunomodulators could be explored, but more research is needed to prove their effectiveness. In the worst cases where patients cannot bear their symptoms and don’t respond to the treatment, surgery could be an option.
Currently, taking medication for a longer period is not encouraged due to the side effects of drugs like budesonide. However, if necessary, the lowest possible dosage should be used, not exceeding 6 mg per day. Patients can have bouts of budesonide treatment to periodically reduce their symptoms as needed.
What else can Collagenous and Lymphocytic Colitis (Microscopic Colitis) be?
Celiac disease, Crohn’s disease, and Irritable Bowel Syndrome (IBS) can all lead to similar symptoms, such as chronic diarrhea.
- Celiac disease can actually be tested for. This is done with blood tests (serologic testing). Sometimes, if the doctor needs more confirmation, a small tissue sample from your small intestine might be taken. This is called a small bowel biopsy and it often shows that the tiny, finger-like parts of the intestine lining (the villi) are flattened.
- Crohn’s disease is a condition that causes inflammation in the bowel. It often results in diarrhea as well. Unique characteristics are unevenly distributed inflammation in the bowel and other symptoms such as perianal disease, which includes anal fissures or fistulas. If you take a tissue sample (biopsy), you’ll often see granulomas and inflammation that goes through the whole wall of the bowel (transmural inflammation).
- IBS is another condition that often comes with diarrhea. But it’s a condition that is usually diagnosed when all other causes for the symptoms have been ruled out (diagnosis of exclusion). Apart from diarrhea, those suffering from IBS often have pain that feels like cramps in their belly, which improves after going to the toilet. People with IBS also often notice a change in the look and frequency of their bowel movements.
It’s important for a doctor to consider these possibilities and perform the necessary tests to make a correct diagnosis.
What to expect with Collagenous and Lymphocytic Colitis (Microscopic Colitis)
Patients with microscopic colitis often experience a chronic pattern of symptoms that can come and go. Diarrhea, a common symptom, can sometimes go away on its own or often improve with treatment within a few weeks. However, symptom relapses are common. Currently, it’s unclear if one form of microscopic colitis is more severe than the other. Importantly, at this time, microscopic colitis is not linked to an increased risk of colorectal cancer.
Possible Complications When Diagnosed with Collagenous and Lymphocytic Colitis (Microscopic Colitis)
The significant issues associated with this disease typically don’t involve worsening disease but are mostly concerned with repeated symptoms. But, the therapy that involves a steroid called budesonide can cause multiple issues if used for an extended time.
Moving towards the problems linked to the therapy, here is a list:
- Steroid therapy complications
- Complications from long-term use of Budesonide
Preventing Collagenous and Lymphocytic Colitis (Microscopic Colitis)
Microscopic colitis is one cause of ongoing or chronic diarrhea. This condition can be confirmed through biopsies, which are lab-tested samples collected during a colonoscopy. Generally, medications are effective in controlling symptoms and inducing remission, but in cases where these aren’t effective, surgery is considered. However, it’s recommended only when symptoms become unbearable.
People with this condition usually experience three or more bowel movements daily, most of which are watery in nature. In some cases, individuals may have more than nine bowel movements daily. The aim of treatment is to reduce this number to three or less daily, and eliminate watery bowel movements.
Some lifestyle choices, such as smoking and use of non-steroidal anti-inflammatory drugs like ibuprofen, are found to trigger this condition. Therefore, patients are advised to quit smoking and reduce or discontinue the use of such drugs. It’s important to note, however, that there’s no known link between microscopic colitis and an increased risk of colon cancer.
While symptoms may return, it’s crucial to monitor them and report any changes for further evaluation.