Oral vancomycin is being increasingly used for treatment of Clostridium difficile infection (CDI), although the feasibility for such approach and avoidance of currently recommended oral metronidazole for mild to moderate (mm)-CDI remain uncertain. We sought to assess treatment response in hospitalized patients with mm-CDI at our university medical center.
Standard Infectious Diseases Society of America and Society for Healthcare Epidemiology of America definitions were used. Primary outcomes included rate of treatment response and infection recurrence following therapy.
Among 513 total cases of CDI between 2011 and 2013, 168 were mm-CDI and were further analyzed. Overall treatment responses to oral vancomycin were 97% versus 82% in patients given metronidazole (P = 0.002). Overall rate of CDI recurrence was 13% following vancomycin versus 9% following metronidazole treatment (P = 0.4). In 85 patients with NAP1 (North American PFGE type 1) CDI, vancomycin and metronidazole yielded similar response (97% vs 98%, P = 0.13), whereas in 83 patients with non-NAP1 CDI, rate of treatment response to vancomycin was higher (98% vs 78% with metronidazole, P = 0.007). In a regression analysis, initial therapy with metronidazole was an independent predictor of treatment failure (odds ratio, 8.4; 95% confidence interval, 1.75–40; P = 0.007) after controlling for hypoalbuminemia (<3 g/dL), concurrent use of proton pump inhibitors, chronic liver disease, community-onset CDI, age older than 65 years, and presence of more than 3 comorbidities. In the subset of 91 patients treated with metronidazole, presence of chronic liver disease (odds ratio, 4.4; 95% confidence interval, 1.19–16.4; P = 0.027) was associated with treatment failure.
Oral metronidazole therapy for mm-CDI in hospitalized patients might not be optimal and needs further reassessment.