Transplantation: Laboratory Testing for Screening and Monitoring Infectious Diseases
Transplantation of solid organs, bone marrow, and other human tissues saves and improves thousands of lives every year. Approximately 40,000 transplants were performed in the United States in 2019.1 Unfortunately, demand exceeds supply—more than 109,000 men, women, and children were on the national transplant waiting list as of September 2020.1
Successful transplants are guided by laboratory testing, including pre- and post-transplant testing for infectious diseases.2-5 An organ or tissue with a latent infection can cause serious illness in the recipient and potentially donor organ or tissue rejection. Immunosuppressant drugs that help prevent rejection of the transplanted organ or tissue can lead to a latent infection becoming active.3,4
This article will discuss the importance of laboratory testing for patients who donate and receive transplants, with a focus on screening and monitoring for infectious diseases.
Overview of Transplantation and the Importance of Laboratory Testing
A transplant performed between 2 different persons is called an allograft transplant; tissue can be from a living or a deceased donor. Laboratory testing is used to determine if donor and recipient tissues are a “match;” examine general parameters of health (eg, tests of liver and renal function); monitor for signs of rejection of the transplanted tissue; and monitor levels of immunosuppressant drugs5-9 (see Sidebar).
Screening for infectious diseases prior to transplant and monitoring the recipient for the development of infections are also critically important to the transplant success.2-5
Donor and Recipient Pre-Transplant Infectious Disease Testing
Donor Testing
To avoid transmission of infectious diseases through the transplanted organ or tissue, the Centers for Disease Control and Prevention (CDC) and Organ Procurement and Transplantation Network (OPTN) require prospective organ and tissue donors be tested for certain infections (Table).3
Similar requirements have been published by professional organizations4 and the United States Food and Drug Administration (FDA).10 Importantly, the FDA requires that infectious disease donor testing be performed using assay kits that are FDA approved or FDA cleared specifically for donor testing and performed according to the manufacturer’s instructions.4 In many cases, the FDA requires that donor specimens be tested by both an antibody test and a nucleic acid amplification test (NAAT or NAT).4
Also important is a detailed donor social and medical history, which can be used to indicate the risk of various infectious diseases and other health problems.11
Recipient Testing
To avoid activation of latent or unrecognized infections by immunosuppressant drugs in transplant recipients, the American Society of Transplantation Infectious Diseases Community of Practice recommends testing for certain infections (Table).4
Post-Transplant Testing
Specific guidelines have been developed for post-transplant testing and vary with the type of transplant performed (eg, a solid organ such as a liver or kidney, or bone marrow transplant).5,8,9,12,13 However, all transplant recipients are at risk of infections and require monitoring for the same types of infectious diseases tested for prior to receiving the transplant.2,5,8,9,12,13 Post-transplant testing (Table) depends on the type of transplant and the recipient’s clinical condition.14
Table. Summary of donor, recipient, and post-transplant infectious disease testing3,4,10,14