This chapter considers aspects of infection unique to patients receiving transplanted organs. The evaluation of infections in transplant recipients involves consideration of both the donor and the recipient of the transplanted organ. Two central issues are of paramount importance: (1) Infectious agents (particularly viruses, but also bacteria, fungi, and parasites) can be introduced into the recipient by the donor organ. (2) Treatment of the recipient with medicine to prevent rejection can suppress normal immune responses, greatly increasing susceptibility to infection. Thus, what might have been a latent or asymptomatic infection in an immunocompetent donor or in the recipient prior to therapy can become a life-threatening problem when the recipient becomes immunosuppressed. The pretransplantation evaluation of each patient should be guided by an analysis of both (1) what infections the recipient is currently harboring, since organisms that exist in a state of latency or dormancy before the procedure may cause fatal disease when the patient receives immunosuppressive treatment; and (2) what organisms are likely to be transmitted by the donor organ, particularly those to which the recipient may be naïve.
A variety of organisms have been transmitted by organ transplantation (Table 132-1). Transmission of infections that may have been latent or not clinically apparent in the donor has resulted in the development of specific donor-screening protocols. Serologic studies should be ordered to detect viruses such as herpes simplex virus types 1 and 2 (HSV-1, HSV-2), varicella-zoster virus (VZV), cytomegalovirus (CMV), Epstein-Barr virus (EBV), and Kaposi's sarcoma–associated herpesvirus (KSHV) as well as hepatitis A, B, and C viruses and HIV. In addition, when relevant, donors should be screened for viruses such as West Nile virus, rabies virus, human T lymphotropic virus type I, and lymphocytic choriomeningitis virus as well as for parasites such as Toxoplasma gondii, Strongyloides stercoralis, Schistosoma species, and Trypanosoma cruzi (the latter particularly in Latin America). Clinicians caring for prospective organ donors should examine chest radiographs for evidence of granulomatous disease (e.g., caused by mycobacteria or fungi) and should perform skin testing or obtain blood for immune cell–based assays that detect active or latent Mycobacterium tuberculosis infection. Evaluation for syphilis should also be performed. An investigation of the donor's dietary habits (e.g., consumption of raw meat or fish or of unpasteurized dairy products), occupations or avocations (e.g., gardening or spelunking), and travel history (e.g., travel to areas with endemic fungi) is also indicated and may mandate additional testing (Table 132-1).
Table 132-1 Common Pathogens Transmitted by Organ Transplantation: Frequent Sites of Reactivation and Diseasea |Favorite Table|Download (.pdf)
Table 132-1 Common Pathogens Transmitted by Organ Transplantation: Frequent Sites of Reactivation and Diseasea