Oral Vancomycin 6-week Taper Regimen is Superior to Metronidazole and Short Course Oral Vancomycin as Treatment for Both Initial and Recurrent Clostridium difficile Infection (CDI)

Background:

CDI is a severe health-care associated infection. Relapse rates of > 20% have been reported when metronidazole or vancomycin is discontinued. Observational studies suggest prolonged, tapering, and pulsed-dosed regimens of vancomycin reduce relapse. Prolonged regimens as initial therapy have not been previously studied. We initiated vancomycin 6-week taper as treatment of choice for first CDI diagnosis in patients ≥ 60 years, patients < 60 years with co-morbidities, and as treatment of choice for patients with a previous history of CDI.

Objective: Compare vancomycin 6-week taper to metronidazole and to short course (≤14 days) vancomycin as treatment for both initial and recurrent CDI.

Methods: We studied all patients in our service area treated for positive C. difficile toxin from June 2007 through September 2009.  In October 2008, our treatment guidelines changed. Vancomycin 6-week taper is now recommended as treatment for first CDI diagnosis in patients age ≥ 60 years and in younger patients with significant co-morbidities.  In addition, vancomycin 6-week taper is now recommended as treatment for any patient with a previous history of CDI, including relapse (defined as recurrence of disease within 3 months).

Results: 1.  In the 16 months prior to change in treatment guidelines, 747 patients were treated for first time CDI.  Relapse occurred in 62/396 (15.7%) treated with metronidazole and in 44/351 (12.5%) treated with short course vancomycin.  An additional 134 patients with a previous history of CDI were treated.  Relapse occurred in 5/19 (26.3%) treated with metronidazole, 7/39 (17.9%) treated with short course vancomycin, and 7/76 (9.2%) treated with vancomycin 6-week taper.

 2.  In the subsequent 12 months after treatment guidelines changed, 471 patients were treated for first time CDI.  Relapse occurred in 7/63 (11.1%) treated with metronidazole, 11/89 (12.4%) treated with short course vancomycin, and in 26/319 (8.2%) treated with vancomycin 6-week taper.  An additional 130 patients with a previous history of CDI were treated.  Relapse occurred in 6/118 (5.9%) treated with vancomycin 6-week taper.

Conclusions: Oral vancomycin 6-week taper regimen outperformed metronidazole and short course vancomycin for both initial and recurrent Clostridium difficile infection.  Oral vancomycin 6-week taper is now our standard of practice.  Only a few patients, typically younger, outpatients, and without co-morbidities, are still treated with other regimens.