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Symptoms and Signs of Clostridium Difficile
(C. difficile, C. diff)

Doctor's Notes on Clostridium Difficile
(C. difficile, C. diff)

Clostridium difficile colitis is an infection of the colon by the bacterium, Clostridium difficile (C. difficile). Colitis refers to inflammation of the large intestine (colon). The inflammation of C. difficile colitis is due to its production of toxins that damage the lining of the colon. The most common cause of C. difficile colitis is treatment with antibiotics, because the antibiotics likely suppress the normal colonic bacteria that keep C. difficile from growing.

Signs and symptoms of C. difficile colitis are diarrhea, abdominal pain, and fever. In severe cases, associated complications can include dehydration, rupture of the colon, and spread of the infection to the abdominal cavity or elsewhere in the body. Severe infection may be life-threatening.

Clostridium Difficile
(C. difficile, C. diff) Symptoms

The symptoms of C. difficile colitis range from mild to severe. Watery diarrhea is the main symptom regardless of the severity of the infection, although it may not be present in every patient.

Some patients are carriers of the organism and do not develop an active infection. These individuals may shed the organism and cause environmental contamination.

Generally, mild C. diff infection (in addition to diarrhea) may result in:

The diarrhea may occur up to 10 to 15 times daily. More severe infections may cause severe and profuse diarrhea, severe abdominal pain, and high fever. Toxic megacolon, which indicates a massively enlarged and distended colon, is a manifestation of severe disease. Severe cases may also be associated with generalized infection (sepsis) resulting in instability of blood pressure and heart rate, as well as disruption of the functions of other body organs (septic shock).

It is not clear why different individuals have different reactions to C. difficile infections.

Clostridium Difficile
(C. difficile, C. diff) Causes

In the colon, the C. diff spores are present in the inactive form. There are numerous different bacteria that typically reside in the colon and make up part of the normal flora of the colon. These bacteria prevent the activation of the C. diff spores into the active bacterial form.

However, when antibiotics are administered for the treatment of an infection, they may kill some of the normal colonic bacteria. This process disrupts the normal balance of gut bacteria and allows Clostridium difficile to become activated and infectious.

When C. diff becomes activated, it produces two different toxins (chemicals), toxin A and toxin B. These toxins may cause inflammation of the inner lining of the colon, resulting in pooling of white blood cells in the colon. If the inflammation is severe, it can result in destruction of the normal cells that line the inside of the colon. When these cells are shed, and a large number of white blood cells may appear as small whitish membranes when visualized by colonoscopy (camera placed inside the colon). These membranes are referred to as "pseudomembranes" because they are not real membranes, thus the name pseudomembranous colitis.

The inflammatory process may result in diarrhea, abdominal pain, fever, and other signs of infection.

It is important to note that not all antibiotics cause C. difficile colitis, and not everyone receiving antibiotics will develop this infection. It is also worth mentioning that diarrhea may occur due to antibiotics for other reasons and that not all antibiotic-associated diarrheas mean that the individual has C. difficile colitis. Many antibiotics can cause diarrhea as a side effect through unknown mechanisms.

Although any antibiotic is a potential risk factor for C. diff infection, the ones most commonly recognized are:

Other risk factors for C. diff infection include:

  • hospitalization,
  • age greater than 65 years,
  • the presence of chronic medical conditions, and
  • severe illness.

Another possible additional risk factor is the suppression of gastric acid.

The Worst Foods in Your Fridge Slideshow

The Worst Foods in Your Fridge Slideshow

Most of us know a dietary disaster when we see it on the menu: a double bacon cheeseburger or a slice of cheesecake. But we often don't realize there are a host of unhealthy foods we eat everyday, right in our refrigerators. These foods can add extra calories, fat, sugar, and salt to your diet without you realizing.

We will review the 10 worst foods you may have in your refrigerator or freezer. Foods on this list are commonplace, high in trans fats, saturated fat, sugar, and/or salt. We will also take look at healthy alternatives suggested by WebMD nutrition expert/writer Elaine Magee.


Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.