Clostridioides (formerly Clostridium) difficile–Induced Colitis

In C. difficile–induced colitis, the bacteria produce toxins that cause inflammation of the colon (colitis), usually after antibiotics are taken to treat an infection. Many antibiotics alter the balance among the types and quantity of bacteria that live in the intestine. Thus, certain disease-causing bacteria, such as C. difficile, can overgrow and replace the harmless bacteria that normally live in the intestine. C. difficile is the most common cause of colitis that develops after antibiotics are taken.

When C. difficile bacteria overgrow, they release toxins that cause diarrhea, colitis, and the formation of abnormal membranes (pseudomembranes) in the large intestine.

A deadlier strain of C. difficile has been identified in some hospital outbreaks. This strain produces substantially more toxin, causes more severe illness with greater chance of relapse, is easier to transmit, and does not respond as well to antibiotic treatment.

Almost any antibiotic can cause this disorder, but clindamycin, penicillins (such as ampicillin and amoxicillin), cephalosporins (such as ceftriaxone), and fluoroquinolones (such as levofloxacin and ciprofloxacin) are implicated most often. C. difficile–induced colitis can occur even after very brief antibiotic courses. C. difficile–induced colitis also may follow the use of certain cancer chemotherapy drugs.

C. difficile infection is most common when an antibiotic is taken by mouth, but it also occurs when antibiotics are injected into a muscle or given by vein (intravenously).

The risk of developing C. difficile–induced colitis and the risk that it will be severe increases with age. Other risk factors include

Medications that decrease gastric acidity include proton pump inhibitors and histamine-2 (H2) blockers, which are used to treat gastroesophageal reflux Gastroesophageal Reflux Disease (GERD) In gastroesophageal reflux disease, stomach contents, including acid and bile, flow backward from the stomach into the esophagus, causing inflammation in the esophagus and pain in the bottom... read more and peptic ulcer disease Peptic Ulcer Disease A peptic ulcer is a round or oval sore where the lining of the stomach or duodenum has been eaten away by stomach acid and digestive juices. Peptic ulcers can result from infection with Helicobacter... read more .

Sometimes the source of the bacteria is the person's own intestinal tract. C. difficile is commonly present in the intestines of newborns, healthy adults, and adults who are hospitalized. In these people, C. difficile typically do not cause illness unless they overgrow. However, these people can spread clostridia to at-risk people. Person-to-person spread can be prevented by meticulous hand washing Prevention of Infection Several measures help protect people against infection. Handwashing is an effective way of preventing the spread of infectious microorganisms from one person to another. Handwashing is particularly... read more .

People may also get the bacteria from pets or the environment.

Colitis caused by C. difficile infection rarely occurs unless people have recently used antibiotics. However, physically stressful events, such as surgery (typically involving the stomach or intestine), can likely lead to the same kind of imbalance among the type and quantity of bacteria in the intestine or can interfere with the intestine's intrinsic defense mechanisms, which, in turn, allows C. difficile infection and colitis to develop.

Symptoms of C. difficile infection typically begin 5 to 10 days after starting antibiotics but may occur on the first day or up to 2 months later.

Symptoms vary according to the degree of inflammation caused by the bacteria, ranging from slightly loose stools to bloody diarrhea, abdominal pain and cramping, and fever. Nausea and vomiting are rare.

The most severe cases (fulminant colitis Complications of Crohn disease ) may involve life-threatening dehydration Dehydration Dehydration is a deficiency of water in the body. Vomiting, diarrhea, excessive sweating, burns, kidney failure, and use of diuretics may cause dehydration. People feel thirsty, and as dehydration... read more , fast heart rate, low blood pressure Low Blood Pressure Low blood pressure is blood pressure low enough to cause symptoms such as dizziness and fainting. Very low blood pressure can cause damage to organs, a process called shock. Various drugs and... read more , and perforation of the large intestine Perforation of the Digestive Tract Any of the hollow digestive organs may become perforated (punctured), which causes a release of intestinal contents and can lead to sepsis (a life-threatening infection of the bloodstream) and... read more .

Doctors suspect C. difficile–induced colitis in anyone who develops diarrhea within 2 months of using an antibiotic or within 72 hours of being admitted to a hospital.

The diagnosis is confirmed by using stool tests. Doctors do tests to detect toxins produced by C. difficile as well as a certain enzyme released by the bacteria. Doctors also do tests such as the polymerase chain reaction (PCR) technique Polymerase chain reaction (PCR) Genetic diagnostic technologies are scientific methods that are used to understand and evaluate an organism's genes. (See also Genes and Chromosomes.) Genes are segments of deoxyribonucleic... read more to detect the presence of the bacteria's genetic material (DNA).

A doctor can also diagnose C. difficile–induced colitis by inspecting the lower part of the inflamed large intestine (the sigmoid colon), usually through a sigmoidoscope Endoscopy Endoscopy is an examination of internal structures using a flexible viewing tube (endoscope). In addition to examinations, doctors can use endoscopy to do biopsies and give treatment. Endoscopes... read more (a flexible viewing tube). If they observe a specific type of inflammation called pseudomembranous colitis, C. difficile–induced colitis is diagnosed. A colonoscope (a longer flexible viewing tube) is used to examine the entire large intestine if the diseased section of intestine is higher than the reach of the sigmoidoscope. These procedures, however, usually are not required.

Doctors may do imaging tests, such as abdominal x-rays X-Ray Studies of the Digestive Tract X-rays often are used to evaluate digestive problems. Standard x-rays ( plain x-rays) can show some blockages or paralysis of the digestive tract, or abnormal air patterns in the abdominal cavity... read more or computed tomography Computed Tomography and Magnetic Resonance Imaging of the Digestive Tract Computed tomography (CT) and magnetic resonance imaging (MRI) scans are good tests for assessing the size and location of abdominal organs. Additionally, cancerous (malignant) or noncancerous... read more (CT), if they suspect a serious complication, such as perforation of the large intestine, fulminant colitis, or megacolon.

If a person with C. difficile–induced colitis has diarrhea while taking an antibiotic, the antibiotic is stopped immediately unless it is essential. After stopping the antibiotic, symptoms usually stop within 10 to 12 days. If the symptoms are severe or persist, people are usually given an antibiotic that is effective against C. difficile.

Most cases of C. difficile–induced colitis are treated with the antibiotic vancomycin or fidaxomicin, given by mouth. Fidaxomicin results in fewer recurrences of symptoms.

Medications (such as loperamide) that people sometimes take to slow the movement of the intestine and treat diarrhea should not be taken. Such medications may prolong or worsen the disorder by keeping the disease-causing toxin in contact with the large intestine.

Occasionally, C. difficile–induced colitis is so severe that the person must be hospitalized to receive intravenous fluids, electrolytes Overview of Electrolytes More than half of a person's body weight is water. Doctors think about water in the body as being restricted to various spaces, called fluid compartments. The three main compartments are Fluid... read more (such as sodium Overview of Sodium's Role in the Body Sodium is one of the body's electrolytes, which are minerals that the body needs in relatively large amounts. Electrolytes carry an electric charge when dissolved in body fluids such as blood... read more , magnesium Overview of Magnesium's Role in the Body Magnesium is one of the body's electrolytes, which are minerals that carry an electric charge when dissolved in body fluids such as blood, but the majority of magnesium in the body is uncharged... read more , calcium Overview of Calcium's Role in the Body Calcium is one of the body's electrolytes, which are minerals that carry an electric charge when dissolved in body fluids such as blood, but most of the body's calcium is uncharged. (See also... read more , and potassium Overview of Potassium's Role in the Body Potassium is one of the body's electrolytes, which are minerals that carry an electric charge when dissolved in body fluids such as blood. (See also Overview of Electrolytes.) Most of the body’s... read more ), and blood transfusions Overview of Blood Transfusion A blood transfusion is the transfer of blood or a blood component from one healthy person (a donor) to a sick person (a recipient). Transfusions are given to increase the blood's ability to... read more .

Rarely, surgery is required. For example, surgical removal of the large intestine (colectomy) may be needed in severe cases as a lifesaving measure.