Epidemiology, risk factors, and outcome of Clostridium difficile infection in heart and heart-lung transplant recipients

Background: Clostridium difficile is a major cause of diarrhea in thoracic organ transplant recipients. We investigated the epidemiology, risk factors, and outcome of Clostridium difficile infection (CDI) in heart and heart-lung transplant (HT) recipients. Methods: This is a retrospective study from 2004 to 2013. CDI was defined by diarrhea and a positive toxigenic C. difficile in stool measured by toxin enzyme immunoassay (2004-2006) or polymerase chain reaction (2007-2013). Cox proportional hazards regression was used to model the association of risk factors with time to CDI and survival with CDI following transplantation. Results: There were 254 HT recipients, with a median age of 53 years (IQR, 45-60); 34% were female. During the median follow-up of 3.1 years (IQR, 1.3-6.1), 22 (8.7%) patients developed CDI. In multivariable analysis, risk factors for CDI were combined heart-lung transplant (HR 4.70; 95% CI, 1.30-17.01 [P=.02]) and retransplantation (HR 7.19; 95% CI, 1.61-32.12 [P=.01]). Acute cellular rejection was associated with a lower risk of CDI (HR 0.34; 95% CI, 0.11-0.94 [P=.04]). CDI was found to be an independent risk factor for mortality (HR 7.66; 95% CI, 3.41-17.21 [P<.0001]). Conclusions: Clostridium difficile infection after HT is more common among patients with combined heart-lung and those undergoing retransplantation. CDI was associated with a higher risk of mortality in HT recipients.