Organ transplantation is life saving, and there is no question that a patient on hemodialysis will have a better quality of life after receiving a kidney transplant. However, these patients are immunocompromised after years of dialysis, and they are subject to years of treatment with immunosuppressant drugs, to prevent rejection of the new organ. This makes the issue of infection as a result of the transplanted organ itself especially critical.
There have been clusters of infections described with transplantation, and recipients have had poor outcomes. Infections have been transmitted to recipients of vascularized organs as well as tissues including bone and cornea.
Although donor screening is utilized, it is often inadequate, because many infectious diseases have a window of time within which the antibodies to the disease are not present. Many lab tests utilized to identify infection rely upon isolation of specific antibodies. To try to identify infections in donors, donor blood, urine, and saliva are cultured for pathogens like bacteria or fungi, and antibody assays are utilized to identify Hepatitis C, B, HIV, organ or tissue during processing .
Donor questionnaires are also utilized to screen for high-risk behaviors or exposure to infectious agents, and the drawbacks of this approach are evident.
The risk for transplant-associated infection has not been calculated, but multiple host and donor factors become important. These include epidemiology of certain infections, and the risk of transmissibility. Since transplant of both tissues and organs are increasing, it is important for researchers to find new methods to identify transmissible organisms, and to standardize procedures for screening donors.
An interesting case was recently published in the New York Times. A Maryland man died of rabies from an infected donor. Doctors did not suspect the donor had rabies, so they did not test for the virus, which is fatal if not treated. The CDC reported another death from rabies in an organ transplant recipient in 2011. This donor had 4 recipients of tissues and corneas, and when one recipient became ill, the other three were contacted and treated successfully before they developed rabies. Testing the donor tissue after the first patient died revealed the same strain of rabies that killed the recipient. Doctors are now questioning whether or not to transplant organs from donors with neurologic diseases that are not understood. There are neurologic diseases due to infectious causes, which may present with symptoms that are not easily linked in early stages to the specific disease.
Transplant infections can be due to nosocomial or hospital acquired infections, as well as from contamination of the tissue or organ, through handling or preparation for transplant. It is important to identify the source of the transplant infection.
An April article published in Transplant Procedures discusses the result of a study of utilization of organs from infected donors. Antibiotic therapy was started in the donor when the infection was identified, and it was continued in the recipient. Perhaps because of the antibiotic therapy, the patients receiving kidneys from donors with common and treatable bacterial infections actually had shorter hospital stays.
However, blood-borne viruses like Hepatitis C and HIV do not lend themselves to treatment. Emerging pathogens may not be identified. And a virus like rabies will not be tested for unless the physician has a high index of suspicion that the donor has been infected with rabies. It is in cases such as these that better screening of donors must be instituted.
Transplantation of organs from patients with cancer is ill advised. In 2010, a doctor knowingly implanted a kidney into a man from a woman with uterine cancer, thinking the chance of cancer in the recipient was negligible. However, the recipient did develop cancer, and had the kidney removed six months later. Three weeks after that, he died of the cancer, and the doctor was later found to be negligent in his duty to protect his patient.
Research is directed at improving screening for infection in donor organs and tissues. In the interim period, it is inevitable that infections will be transmitted occasionally. Unfortunately, some bloodborne infections are not easily treated. However, risk-benefit analysis falls on the side of transplantation to improve mortality and quality of life in many recipient patients.