Người nhận ghép tạng được ức chế miễn dịch cho một loạt các này bao gồm sử dụng thuốc ức chế miễn dịch để giảm thiểu từ chối cấy ghép, các rào cản niêm mạc bị hỏng (ví dụ, từ ống thông đường tiểu), | 6 Infectious Disease 153 Organ Transplantation Organ transplant recipients are immunosuppressed for a variety of These include use of immunosuppressive drugs to minimize rejection of the transplant broken mucocutaneous barriers . from catheters infection with immunomodulating viruses . CMV Epstein-Barré virus hepatitis B and C viruses HIV and metabolic derangements. In general the approach to infection in the organ transplant recipient is similar to that already outlined for immunocompetent patients. Pulmonary infection is known to be the most common infection encountered in this group. The risk should be stratified by time from transplantation. In the first month after transplant the vast majority of infections are nosocomial bacterial infections of the lungs or candidal and bacterial wound urinary tract or vascular catheter infections. The approach to each has already been outlined. In the period from 1 to 6 months after transplant the doses of immunosuppressive drugs are higher than in ensuing months and many of the immunomodulatory viruses reactivate endogenously or from the transplanted organ. When CMV is transplanted with the solid organ into the previously non-immune host it reactivates in that organ and causes clinical disease in the recipient. In concert with this reactivation opportunistic pathogens emerge including Listeria monocytogenes Nocardia asteroides Mycobacterium tuberculosis Pneumocystis carinii Asperillus fumigatus Cryptococcus neoformans and far less commonly than in AIDS Toxoplasma gondii. In the recipient of a bone marrow allograft CMV reactivates and replicates in pulmonary macrophages. The engrafted marrow recognizes pulmonary macrophages which are supporting replication of CMV as being more foreign and hence CMV pneumonitis parallels graft versus host disease. Once the recipient has survived 6 months past the transplant date the risk of infection is similar to the general population with the exception of those undergoing
