Risk factors for infection with carbapenem-resistant Klebsiella pneumoniae after liver transplantation: the importance of pre- and posttransplant colonization.

Improved understanding of risk factors associated with carbapenem-resistant-Klebsiella pneumoniae (CR-KP) infection after liver transplantation (LT) can aid development of effective preventive strategies. We performed a prospective cohort study of all adult patients undergoing LT at our hospital during 30-month period to define risk factors associated with CR-KP infection. All patients were screened for CR-KP carriage by rectal swabs before and after LT. No therapy was administered to decolonize or treat asymptomatic CR-KP carriers. All patients were monitored up to 180 days after LT. Of 237 transplant patients screened, 41 were identified as CR-KP carriers (11 at LT, 30 after LT), and 20 developed CR-KP infection (18 bloodstream-infection, 2 pneumonia) a median of 41.5 days after LT. CR-KP infection rates among patients non-colonized, colonized at LT, and colonized after LT were 2%, 18.2% and 46.7% (p < 0.001). Independent risk factors for CR-KP infection identified by multivariate analysis, included: renal-replacement-therapy; mechanical ventilation > 48 h; HCV recurrence, and colonization at any time with CR-KP. Based on these four variables, we developed a risk score that effectively discriminated patients at low versus higher risk for CR-KP infection (AUC 0.93, 95% CI 0.86-1.00, p < 0.001). Our results may help to design preventive strategies for LT recipients in CR-KP endemic areas.