Clostridium difficile disease: diagnosis and treatment

Clostridium difficile is the most common nosocomial pathogen of the gastrointestinal tract. Disease is usually a consequence of antibiotic therapy, but sporadic cases do occur. Cytotoxin assay for toxin B remains the gold standard for confirming diagnosis. Several rapid enzyme immunoassay tests are available, but specificity and sensitivity vary; a negative test may not exclude disease. Oral metronidazole 250 to 500 mg four times a day is the recommended first-line therapy; vancomycin (125 mg four times a day) should be reserved for patients who cannot tolerate metronidazole, who do not respond to this drug, or who should not take it for various reasons (i.e., pregnancy). Recurrent C. difficile disease is a difficult problem. The nonpathogenic yeast Saccharomyces boulardii has been shown in controlled trials to be effective in reducing recurrences when given as an adjunct to standard therapy. Prevention of epidemics relies on careful hand washing and environmental decontamination.