Oral Vancomycin for Clostridium Difficile Prophylaxis in Autologous Stem Cell Transplant
Background/Rationale: Clostridium difficile infection (CDI) is a concerning cause of diarrhea in the stem cell transplant population. An incidence of CDI in up to 15% of autologous stem cell transplant (ASCT) patients has been reported. There are also potential risk factors associated with CDI. Previous literature has shown efficacy of oral vancomycin in preventing CDI in the allogeneic stem cell transplant population. We evaluated whether this can also be demonstrated in the autologous patients.
Objectives: The primary objective was to determine CDI before and after implementation of oral vancomycin prophylaxis in ASCT patients. The secondary objective was to compare known risk factors between the groups. These risk factors included type of malignancy, use of broad spectrum antibiotics, and use of proton pump inhibitors. Comparisons also included length of stay (LOS).
Methods: A retrospective chart review was conducted to assess the incidence of CDI using no prophylaxis versus vancomycin prophylaxis in adult ASCT patients at Aurora St. Luke’s Medical Center, Milwaukee, WI, USA. The prophylaxis regimen consisted of vancomycin solution 125 mg by mouth twice daily which started on day of admission until the patient was discharged. Eighty-one unique patients received ASCT during a hospital admission between January 2015 and December 2017, of which 32 patients received vancomycin prophylaxis starting in January 2017. Treated malignancies included 35 lymphoma and 56 multiple myeloma patients. Mean age was 62 years-old. Testing was for the Clostridium difficile toxin B gene, which was detected by nucleic acid amplification. The Fischer’s exact test was used to assess endpoints.
Results: Incidence of Clostridium difficile infection was seen in 9 patients (15.3%) in the group without prophylaxis. This was compared to one case of CDI in the patients receiving prophylactic vancomycin (3.1%), p-value = 0.09. No significant differences were demonstrated with age, use of quinolones/clindamycin, use of proton pump inhibitors, or malignancy type when compared to presence of CDI. LOS between the CDI versus the no CDI group was 21.8 days versus 17.8 days, p-value = 0.09. Median time to diagnosis was 10.1 days.
Conclusions/Discussions: We identified a decrease in Clostridium difficile infection rates in our autologous stem cell transplant population. Interestingly, in the prophylaxis arm, there was one patient with CDI. It was questionable as to if this patient had pre-existing infection on admission. Nonetheless, given our small sample size, we will continue to collect data. Prevention of CDI can potentially lead to benefits that include decreased patient care costs, and decreased length of stay in the hospital.