Molecular monitoring of Candida albicans infections in liver transplant recipients

This report describes the use of the 27A probe for the molecular monitoring of Candida albicans infections in liver transplant recipients. Nosocomial candidiasis is the major fungal infection in liver transplant recipients, with Candida albicans being the species most frequently isolated. The molecular epidemiology of Candida albicans infections has been widely investigated, but scant attention has been focused on monitoring the identity of infecting strains in individual patients over the entire course of their hospitalization. In the study presented here, a total of 179 Candida albicans isolates were collected from 10 liver transplant recipients during multiple surveillance cultures performed before and after liver transplantation and from three healthcare workers at the Transplant Unit of Ospedale di Cisanello, Pisa (Italy). Computer-aided analysis of the 27A-probed DNA fingerprints, used to compare the genetic relatedness of all the Candida albicans isolates, showed that most of the patients colonized with Candida albicans before transplantation harbored a unique Candida albicans genotype. This genotype persisted over the entire course of hospitalization and caused multiorgan failure in two patients, both of whom died from endogenously borne Candida albicans infections. Nosocomial acquisition of Candida albicans strains could be monitored in a timely manner in the other patients; for some of them, subsequent strain replacement was registered at different body sites during the post-transplant period. Neither cross-infection between patients nor transmission from health-care workers to patients occurred in this hospital setting. These results indicate that the molecular monitoring of Candida albicans strains isolated from liver transplant recipients during their hospitalization may provide timely information about the identity of individual Candida albicans strains causing infections.