Clostridium difficile
last authored: March 2010, David LaPierre
last reviewed:
Introduction
The Case of...
Epidemiology
Five-ten percent of population is colonized.
Classification and Characteristics
C. difficile produces A and B toxins, also known as enterotoxin and cytotoxin, respectively. Both are responsible for diarrhea and inflammation, altough their relative roles are currently unknown.
Transmission and Infection
Fecal-oral spread of spores; can survive for one month.
Hospitals are one of the most common
Clinical Manifesations
Causes diarrhea diagnosed by clinical history of antibiotic use (especially broad-spectrum clindamycin), coupled with toxin screening.
Diagnosis
Diagnosis is primarily made by identifying the presence of C. difficile toxin. This is often done using cytotoxicity testing. Stool is filtered, centrifuged, and treated with broad-spectrum antibiotics to kill all bacteria. The resulting supernatant is incubated with two wells of tissue culture cells, one treated with antitoxin against the cytotoxin (A) and one with only supernatant (B). Cell death in B, but not A, suggests the presence of toxin.
Treatment
Antibiotics for anaerobes. Metronidazole first-line for community-acquired C. diff.
Vancomycin orally or IV (125 mg QID) is often used for hospital-acquired C. diff., due to conserns of the NAP1 strain.
Relapse rates are high, especially after many infections.
There is some evidence that probiotics may be useful in preventing disease-associated symptoms, though ongoing treatment is likely required.
Resources and References
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