Clostridium Difficile Infection With Inflammatory Bowel Disease

Infection with this bacteria may worsen Crohn's disease or ulcerative colitis

The human digestive tract is filled with a variety of different types of bacteria. There’s a balance to how much of each type of bacteria is present in any particular person. Some of the bacteria is beneficial and has a specific job to do in helping digest food. Other types, however, can cause illness if their numbers grow to be too numerous. One of those problematic types of bacteria is Clostridium difficile (C. difficile). Infections with C difficile may cause symptoms such as extreme diarrhea, fever, nausea, and inflammation of the colon. When an infection with C. difficile occurs in someone who is living with inflammatory bowel disease (IBD, which includes Crohn’s disease, ulcerative colitis, and indeterminate colitis), the illness can be quite serious and long-lasting.

For people who live with IBD and are already affected by severe disease and who may be receiving medications that suppress the immune system, an infection with C. difficile is a particularly difficult problem. This article will address C. difficile infection including how common it is, how it might be acquired, who with IBD is most at risk, and how it is most frequently treated.

The Microbiome

The bacteria found in the human digestive tract, the microbiome, is extraordinarily complex and still not well understood. The bacteria in the digestive tract help us digest food, but also produce vitamins, affect the immune system, serve as a communication vehicle within the digestive tract, and have other effects.

It is increasingly being understood how diverse the bacteria in the human body are and how important it is that they are in balance. What is not well understood is what that balance may consist of, and how to achieve or sustain that harmony, because the microbiota is different from person to person. 

So far, scientists have identified 1000 species of bacteria in the human digestive tract. However, we also know that this is not all of them; there are more that have yet to be found and analyzed. In addition, it might be that specific parts of the digestive tract have their own mini-ecosystem of bacteria within the larger microbiome.

When the bacteria in the digestive system are imbalanced it is called dysbiosis. Some digestive conditions, including IBD, have been associated with dysbiosis which may be related to disease severity or the need for surgery as a treatment, and the formation of complications such as abscesses. How the microbiome affects us, how we can affect it, and how to keep it in balance are significant areas of ongoing study.

Clostridium Difficile

C. difficile is a type of bacteria that is found in soil but also in the human digestive tract. It produces toxins which can disrupt other cells and kill them. The overgrowth of C. difficile in the human digestive tract causes symptoms such as severe diarrhea and can lead to life-threatening consequences. In addition, it’s being increasingly understood how the effects of this infection can reach beyond the digestive tract and also affect other body systems. 

Antibiotic-associated diarrhea is a type of digestive condition that occurs after receiving treatment with antibiotics. Antibiotics have led to a significant decrease in deaths from infections but they can have adverse effects. Antibiotics kill bacteria: they don’t know the difference between the kind that’s needed by the body and the kind that’s causing an infection. When the good bacteria is killed, it leaves the body open to a takeover by the harmful types of bacteria. The result can be antibiotic-associated diarrhea and it’s estimated that between 15% and 25% of cases are a result of an infection with C. difficile.

C. difficile infection is the most common infection that people get while they are in a hospital setting (which is called a nosocomial infection) in the United States. C. difficile passes easily from person to person, so it can spread quickly in long-term care facilities and hospitals and may be difficult to contain.

Risk Factors for C. Difficile Infection

One important risk factor for developing an infection with C. difficile is the use of antibiotics. In particular, when broad-spectrum antibiotics are used, much of the flora in the digestive tract is killed. The “good” bacteria that keep C. difficile from growing out of control are no longer able to do their job. This gives C. difficile an opening in which to grow out of control and cause disease. 

People who are at risk for developing severe C. difficile infection and poor outcomes include those who are over the age of 70, those who have an obstruction in the small intestine, ileus (a slowdown or stop of the muscle contractions in the intestine), inflammation in the colon that can be seen on a CT scan, and certain other abnormalities that show up on the results of a blood test. People with IBD who have disease in their colon (which is called colitis) are considered to be the ones at the greatest risk. However, it should also be addressed that an infection or a severe infection may also occur in people who are considered to be at low risk.

Why C. Difficile Infection Can Complicate IBD

Infection with C. difficile is a serious problem for anyone but it is shown to be a particularly significant problem with far-reaching effects for people with Crohn’s disease or ulcerative colitis. While C. difficile infection is increasing across the world in recent decades, it is also becoming more prevalent in people with IBD.

One reason for the increasing problems with C. difficile is because there is a newer strain of the bacteria that has been shown to be more harmful. People with IBD who develop C. difficile infection tend to be younger than those in the general population and may go on to have more problems and recurrences of infection. The year after battling an infection, people with IBD have been shown to also have more need for medical treatment. Alarmingly, because this infection can become so severe, people with IBD are also at an increased risk of death. 

There have been outbreaks of C difficile infection at different medical institutions which treat patients with IBD. What was seen in one of these hospitals according to a report from a physician that worked at the facility, was that patients with IBD who developed C. difficile infections were more likely to experience a severe flare-up. Patients with ulcerative colitis, which causes inflammation in the colon, were seen to be at greater risk of infection. People with IBD who develop a C difficile infection have also been shown to be at an increased risk of having colectomy surgery (removal of the colon).

One reason why it’s thought that people with IBD may be more susceptible to C. difficile infection is that the microbiome is already in dysbiosis. It is an active area of study as to why the microbiome is different in people with IBD. While there are some theories, there are still no conclusions that can be made or a plan of action to address the imbalance in the microbiome with treatment.

A second reason is that medications that suppress the immune system are often used to treat IBD, which leaves some patients less able to fight off infection. In particular, receiving corticosteroids, immunomodulators, or 5-amino-salicylates (5-ASA) drugs, which are all commonly used to treat IBD, were shown to be risk factors for developing a C. difficile infection. 

An infection with C. difficile causes what’s called infectious colitis (colitis meaning inflammation in the colon). For people with IBD who are already experiencing or are at risk of experiencing inflammation in the colon may face escalating levels of symptoms from two different disease processes.

For physicians who treat patients with IBD, it is important to identify the C. difficile infection early and make the distinction from an IBD flare-up. The symptoms, including diarrhea and abdominal pain, may be similar, so it’s not easy to tell the difference between the two conditions.

Treating a patient for an IBD flare-up with the usual medications used for this purpose when there is really a C. difficile infection might cause more severe disease. For that reason, physicians might test for infection first prior to starting medications or making a change in medications for what is at first thought to be an IBD flare-up.

Diagnosing C. Difficile Infection in IBD

One of the most important factors in recovering from an infection and not experiencing more severe disease is in getting an early diagnosis. Some of the findings on laboratory tests can be similar for both IBD and C. difficile infection, including a higher white blood cell count, low albumin levels, and high white blood cells in the stool. However, endoscopic tests, such as a colonoscopy, will not show any of the typical things that are seen with IBD, when there is an infection with C. difficile.

The American College of Gastroenterology recommends that all patients with IBD for a suspected flare-up be tested for infection. Several different types of stool tests may be used to diagnose C. difficile infection; hospitals will have their preferred way of testing. It’s currently thought that these tests which are used in people who don’t have IBD are just as effective at identifying infection in those who do have IBD.

Symptoms of infection with C. difficile include :

  • Abdominal tenderness
  • Diarrhea (loose, watery stools for several days)
  • Fever
  • Loss of appetite
  • Nausea

Treating C. Difficile Infection in IBD

Treating the infection in people with IBD will include several steps. During this entire process, it is important that hand-washing and other methods to control infection be used in order to prevent the C. difficile from spreading to other people.

The first step is that if the C. difficile infection was thought to have started because of the use of antibiotics, those antibiotics may need to be stopped. Because C. difficile infection is caused by bacteria, however, a different type of antibiotic may need to be started to clear it. Currently, the only antibiotics approved for C. Difficile are Flagyl (metronidazole, oral or intravenous) and oral Dificid (fidaxomicin).

Other things that may need to be done include giving fluids (intravenously, if the patient is hospitalized) to combat all the water that is being lost through diarrhea. 

As far as continuing treatments for IBD during treatment for the infection, there’s no good evidence as to how to proceed. However, the American College of Gastroenterology suggests that current treatments should be kept as-is but no new immunosuppressive treatments should be started or increased.

Fecal microbiota transplantation (which is also called intestinal microbiota transplantation, or IMT) is a therapy that is in use for the treatment of C. difficile infection. During this treatment, stool from a donor is transferred to the digestive tract of someone who has the infection. This is not done in many places in the country and there’s not a lot of evidence for its use in patients with IBD. However, one small study showed it was effective but the authors think that there’s some potential for the treatment and more research is needed.

A Word From Verywell

An infection with C. difficile can occur after treatment with antibiotics or could be contracted in the hospital or could occur for none of these reasons. It’s clear that this is a special problem for people IBD and can lead to serious and long-term problems. For this reason, it’s important for patients and their medical team to think about C. difficile infections as a potential cause of new symptoms such as watery diarrhea. It’s not easy to tell if there is an infection from symptoms alone, so validated and approved stool testing may be the best course of action. For those who have concerns about developing an infection with C. difficile, it’s important to talk with a gastroenterologist about the specific risk of infection and if anything might be done to prevent it. 

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