Clostridium difficile Infection

Clostridium difficile is a gram-positive anaerobic bacillus which secretes toxins (A and B) that cause diarrhea and pseudomembranous colitis. C. difficile is the most common infectious cause of nosocomial diarrhea. Transmission occurs through contact with contaminated persons and surfaces. The bacterium produces endospores that are able to survive stomach acid and reach the colon.

C. difficile colonizes the intestinal tract after the normal intestinal flora has been disrupted by antibiotic therapy. Susceptibility is increased with broad-spectrum antibiotics, including clindamycin, cephalosporins, ampicillin, amoxicillin, and fluoroquinolones. Pseudomembranous colitis is an inflammatory bowel disorder in which yellowish plaques form over the damaged intestinal mucosa.

Clinical presentation includes fever, crampy abdominal pain, and diarrhea. Severe cases may progress to leukocytosis, dehydration, and toxic megacolon. Diagnosis is confirmed via stool assay detecting the toxin. Pseudomembranes may be visualized on sigmoidoscopy.

Treatment involves discontinuing the causative antibiotic. Oral metronidazole is first-line therapy for cases unresponsive to conservative management. Severe cases may require oral vancomycin. Surgical intervention (total colectomy) is reserved for complications such as toxic megacolon or perforation.