C. difficile colitis can be caused by almost any antibiotic that disrupts the bowel flora, but it’s classically associated with clindamycin (Cleocin) use. Symptoms are caused by the exotoxins produced by the organism. Toxin A is an enterotoxin, and toxin B is a cytotoxin.

C. difficile is most often transmitted directly from patient to patient by the contaminated hands of health care workers; it may also be spread indirectly by contaminated equipment such as bedpans, urinals, call bells, rectal thermometers, nasogastric tubes, and contaminated surfaces such as bed rails, floors, and toilet seats.

Complications of C. difficile include electrolyte abnormalities, hypovolemic shock, anasarca, toxic megacolon, colonic perforation, peritonitis, sepsis, hemorrhage, and death.

The patient may have a history of a recent hospitalization or antibiotic therapy. He or she may be asymptomatic or may exhibit any of the following symptoms: soft, unformed, or watery diarrhea (more than three stools in a 24-hour period) that may be foul smelling or grossly bloody; abdominal pain, cramping, or tenderness; nausea and vomiting; and fever. If toxic megacolon develops, the patient may develop increasing abdominal pain and show signs of septic shock (tachycardia, hypotension, oliguria, and tachypnea).

In nearly 20% of people infected with C. difficile, withdrawing the causative antibiotic is the only necessary treatment. In the other 80%, oral metronidazole (Flagyl) is required in addition to withdrawing the causative antibiotic. Vancomycin (Vancocin) may be used if metronidazole has been ineffective.