Solid-Organ Transplant Recipients
Risk Factors
Immunosuppressive therapy and corticosteroids, particularly when used to treat acute rejection, are once again the cause of the immune defect predisposing organtransplant recipients to fungal infection. Cyclosporine and tacrolimus specifically affect T lymphocytes by decreasing CD4+ helper cells and IL-2 synthesis. Underlying disease and the presence of immunomodulating viral infections such as CMV are also important risk factors affecting neutrophil and macrophage function. The extensive surgery and invasive intensive-care procedures involved in treatment of this patient population mean that environmental factors such as impaired host barriers are of paramount importance in the risk of infection.
The transplanted organ is rarely a source of fungal infection, although this has been reported.
Incidence and Mortality Serious fungal infections can follow solid-organ transplantation and are associated with high mortality (27% to 77%) [33]. Incidence and timing of the infection vary according to the immunosuppressive treatment and type of organ transplanted [29, 34]. Retrospective analyses of organ-transplant outcomes reveal significant levels of fungal infection [34]. In one center for liver transplantation, the rates of disseminated candidiasis, aspergillosis, and combined infection were 6.5%, 7.2%, and 2.6%, respectively. Mortality rate was 80%, with only 1 of the 11 patients with aspergillosis surviving [35]. In 200 episodes of serious infection in 73 heart-lung recipients, reported [36] fungal infections were 14% (12 episodes of candidiasis and 14 episodes of aspergillosis). Cryptococcal infection after solid-organ transplant has been estimated to occur in up to 4% of renal-transplant recipients, with a direct mortality of 36% [37]. Zygomycetes have been reported to cause infection in 1% to 9% of transplant patients, and infection with endemic mycoses depends on the geographic exposure of transplanted patients either before or after the transplant [33].
Course Number: V035B.043001
This CME Expires on July 1, 2003; no tests will be accepted after this date.
This course is accredited by
The University of Pittsburgh School of Medicine, Center for Continuing Education
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