Anaerobic, spore-forming, large Gram-positive bacilli, box-car shaped
Nosocomial > community onset diarrhea usually after taking antibiotics.
Can occur in outbreaks.
Recurrence is very common therefore previous history of C. difficile is a risk factor.
Antacids, especially proton-pump inhibitors, and chemotherapy also increase risk.
Wide range of symptoms possible, and 15% are asymptomatic
Profuse, watery diarrhea
Pseudomembranous colitis or toxic megacolon
Normal colonizer in infants
Probiotics may be helpful. In refractory cases, Fecal Microbiota Transplantation (FMT) is indicated and, very frequently, curative.