Master Clostridioides difficile (Clostridium difficile) with Picmonic for Medicine

This bacteria stains gram-positive, which means that it retains large amounts of the Gram stain due to its high peptidoglycan content in the cell wall.

These bacteria are rod-shaped.

These bacteria prefer to grow in an anaerobic environment.

Broad spectrum antibiotics and those with significant anaerobic activity, especially clindamycin and ampicillin, are associated with C. difficile infection. This is because these antibiotics destroy normal gut flora, allowing C. difficile to proliferate instead.

Toxin A is an enterotoxin released by C. difficile that damages the brush border of the gut. This toxin can eventually be detected in the stool for diagnosis.

Toxin A is an enterotoxin released by C. difficile that damages the brush border of the gut, leading to malabsorption and severe diarrhea.

Toxin B is a cytotoxin released by C. difficile that induces actin depolymerization, leading to damage of the cytoskeletal structure.This toxin can eventually be detected in the stool for diagnosis.

Toxin B induces actin depolymerization, leading to damage of the cytoskeletal structure and cell death. This results in significant inflammation within the bowel wall, leading to bleeding and overall gut dysfunction.

Watery diarrhea is a common symptom of C. difficile infection. Any patient in the hospital with new onset of severe watery diarrhea after antibiotic use should be evaluated for a C. difficile infection.

The toxin production by C. difficile induces significant inflammatory cell invasion into the bowel wall. This inflammation produces pseudomembranes on the bowel lumen which can be seen on gross examination, leading to the term pseudomembranous colitis. Other symptoms include fever, bloody diarrhea, and abdominal pain.

In severe cases of pseudomembranous colitis, excessive inflammation and loss of gut motility can lead to extreme dilation of the colon. This life-threatening complication is known as toxic megacolon. These patients are at high risk for bowel perforation and shock.

Because this bacteria is part of the normal gut flora in many patients, C. difficile infection should be diagnosed via detection of toxins in the stool as opposed to culture.

In mild-to-moderate cases, oral metronidazole has good activity against anaerobic bacteria. However, it is no longer recommended as first-line therapy for adults.

Vancomycin has good gram positive activity and is therefore another option for the treatment of C. difficile infection. It is first line in cases of severe disease, specifically. When used to treat C. difficile, vancomycin is administered orally because intravenous administration does not achieve minimum therapeutic concentration in the gut lumen. Other treatment options for recurrent disease include the antibiotic fidaxomicin, as well as performing a stool transplant to replenish normal gut flora.