Risk factors for the development of Clostridium difficile infection in adult allogeneic hematopoietic stem cell transplant recipients: A single-center study in Québec, Canada

Background: Clostridium difficile infection (CDI) is a significant complication of allogeneic hematopoietic stem cell transplantation (allo-HSCT). Our primary objective was to determine risk factors for the development of CDI during the first year following allo-HSCT. Methods: A matched case–control study nested in a cohort of allo-HSCT at a single hospital in Montréal, Québec, Canada, was conducted from 2002 through 2011. Results: Sixty-five of 760 patients who underwent allo-HSCT between 2002 and 2011 developed CDI, representing an incidence of 8.6%. We selected 123 controls matched for year of transplant for risk factor analyses. In the multivariable analysis, receipt of trimethoprim-sulfamethoxazole (TMP-SMX) prior to transplantation (adjusted odds ratio [aOR] 0.07, 95% confidence interval [CI] 0.02-0.27), mucositis (aOR 5.90, 95% CI 2.08-16.72), and reactivation of cytomegalovirus (CMV) (aOR 6.17, 95% CI 2.17-17.57) and of other Herpesviridae viruses (aOR 3.04, 95% CI 1.13-8.16) were the variables that remained statistically associated with CDI. High-risk antibiotic use in the late post-transplant period (aOR 7.63, 95% CI 2.14-27.22) was associated with development of late CDI. Conclusion: This study revealed reactivation of CMV and other Herpesviridae viruses as novel risk factors for CDI. Administration of TMP-SMX prior to transplantation was independently associated with a decreased risk of CDI. Early and late CDI after HSCT may have distinct risk factors.