Cryptococcosis in organ transplant recipients: An overview

Cryptococcosis is the third most common invasive fungal infection in organ transplant recipients after candidiasis and aspergillosis. Reports indicate that cryptococcosis usually presents as symptomatic disease, and despite therapy the mortality remains high. In addition, some data suggest that there might be differences in the incidence and clinical manifestations of cryptococcosis, depending on the specific transplant organ. The incidence of cryptococcosis in our transplant center is significantly higher in heart transplant recipients than in other transplant groups (p = 0.0001). Although the primary risk factor contributing to cryptococcosis in organ transplant recipients is probably the immunosuppressive therapy used to prevent allograft rejection, environmental factors may also play a role. This is indicated by studies that demonstrate differences in the rate of cryptococcosis according to geographic region. Moreover, data point out differences in the isolation of the fungus from soil samples with higher concentrations of Cryptococcus in areas frequented by birds or contaminated by bird droppings. Therefore, it is prudent to recommend that organ transplant recipients avoid birds or areas contaminated with bird droppings. The current review provides an overview of the changes in the incidence, clinical manifestations, and management of cryptococcosis in organ transplant recipients.