Pre-Transplant Testing and Screening

Pre-transplant testing and screening is the panel of investigations performed during candidacy evaluation to characterize a patient's baseline state and to detect conditions that would alter, delay, or contraindicate transplantation. It includes immunologic typing and antibody screening, infectious-disease serologies, malignancy screening, and organ-specific tests. The aim is to establish a safe baseline and to identify barriers that can be treated before transplantation.

Definition

Pre-transplant testing and screening is the set of laboratory, serologic, immunologic, and imaging investigations used during candidacy evaluation to establish a recipient's baseline and to detect infections, malignancies, and immunologic barriers relevant to transplantation.

Scope

This topic covers the categories of pre-transplant investigation: immunologic (blood typing, HLA typing, panel-reactive antibody and crossmatch), infectious serologies and latent-infection screening, age- and risk-appropriate malignancy screening, and general medical work-up. It excludes the dedicated cardiovascular risk assessment (a separate topic) and post-transplant surveillance. It describes what is tested and why, not which tests to order for an individual.

Core questions

• What immunologic typing and antibody testing characterize the recipient and predict compatibility?
• Which infectious-disease serologies and latent-infection screens are performed before transplantation?
• What malignancy screening is appropriate for transplant candidates?
• Which findings should be treated or resolved before transplantation proceeds?

Key concepts

• ABO blood typing
• HLA typing
• Panel-reactive antibody (PRA) and sensitization
• Crossmatch
• Infectious-disease serologies
• Latent infection screening
• Malignancy screening
• Donor-recipient compatibility

Mechanisms

Immunologic testing characterizes the recipient's HLA antigens and detects preformed anti-HLA antibodies, because prior sensitization (from transfusion, pregnancy, or prior transplant) raises the risk of antibody-mediated rejection; the crossmatch tests recipient serum against donor cells to detect incompatibility before implantation. Infectious screening identifies latent or chronic infections (such as viral hepatitis, tuberculosis exposure, and herpesviruses including cytomegalovirus and Epstein-Barr virus) that can reactivate or transmit under immunosuppression, allowing donor-recipient matching and prophylaxis planning. Malignancy screening seeks active cancer that would contraindicate immunosuppression.

Clinical relevance

Pre-transplant screening establishes the immunologic and infectious baseline that guides organ matching, prophylaxis, and surveillance after transplantation, and it identifies conditions that must be addressed before listing. The KDIGO candidate guideline and systematic reviews of cancer screening describe the categories typically assessed. This topic explains the rationale for screening and is not a directive on testing an individual patient.

Epidemiology

Latent infections such as tuberculosis and chronic viral hepatitis, and herpesvirus seropositivity, are common in candidate populations and inform pre-transplant screening and post-transplant prophylaxis. Cancer screening practices in candidates are summarized in systematic reviews of guideline recommendations.

Evidence & guidelines

The 2020 KDIGO candidate guideline outlines immunologic and infectious screening for kidney transplant candidates; a 2017 systematic review by Acuna and colleagues synthesizes cancer-screening recommendations across solid-organ transplant guidelines. Reviews of transplant infection (Fishman, 2007) inform the infectious-screening rationale.

Debates

How intensive should cancer screening be in transplant candidates?

Guideline recommendations for pre-transplant cancer screening vary in intensity and consistency, and the balance between detecting occult malignancy and avoiding harm or delay is debated.

Seminal works

• chadban-2020
• fishman-2007
• acuna-2017

Frequently asked questions

Why are infectious-disease serologies done before transplantation?

Latent or chronic infections can reactivate or be transmitted under immunosuppression, so serologic screening lets the program plan donor-recipient matching, prophylaxis, and post-transplant surveillance.

What does a positive crossmatch indicate?

It indicates that the recipient has antibodies reactive against the donor, signalling a higher risk of antibody-mediated rejection and influencing whether that donor-recipient pairing should proceed.