Guidance

Chapter 15: exceptional use of organs and tissues from donors potentially or known to be infected

Updated 21 May 2024

Derogation of exclusion criteria for donors who carry an infection risk

We acknowledge the overwhelming clinical need for, and shortage of, organs suitable for transplantation in the UK. The unnecessary loss of potential organs needs to be avoided at all times and has been addressed in part by the guidelines for testing described in previous chapters.

We accept that there may be clinical need for transplantation of such urgency that it may be appropriate to consider the use of organs and tissues for life-preserving purposes from donors who would not otherwise be considered eligible to donate, due to a known or perceived infection risk. Potential organs from such donors should be offered to the transplant community. Fully informed consent to such a procedure is required from the recipient of such transplantation and all measures for risk reduction, including onward transmission, must be taken. Transplants of this nature are likely to be infrequent. Intensive immediate post-transplant monitoring and long-term follow-up of the infection status of recipients should be set in place and the long-term outcome of the recipient recorded centrally by the transplant community.

Matching infection status of donor and recipient

Usually any reactivity in one or more of the mandatory marker assays used for screening donors renders the donor ineligible and the potential donations unsuitable for use without any leave to alter this decision. This is exemplified by the protocols surrounding the practice of blood transfusion and the exclusion of ‘risk donors’. In principle the same applies to any donor of tissues and organs although, as we discuss below, in truly life-preserving situations, relaxation or even derogation of this exclusion may be possible, in particular in situations of discordant serological results in the donor.

Where a donor sample is repeatedly reactive in one assay and is unreactive in one or more assays of similar sensitivity, the likelihood of subsequent confirmatory testing indicating this initial reactivity to be specific is very low. If testing laboratories have evidence based and validated SOPs which indicate such discordant reactivity is likely to be non-specific, only then can consideration be given to disregarding the discrepant repeat reactivity in terms of allowing donation.

The risk of transmission of a pathogen may be reduced or eliminated through the use an organ from a donor who is known to be infected, or at risk of infection, with a pathogen into a recipient infected with the same pathogen (infection match).

Similarly, previous infection or immunisation may decrease or remove the risk of infection following the use of a transplant from a donor who is known to be infected, or who is potentially infected. This approach involves matching of the immune status of the recipient to the infection status of the donor. For example, a recipient shown to be immune to hepatitis B, naturally or by immunisation, is unlikely to suffer re-infection should the transplant be taken from an HBV-infected donor. In this type of matching, it is essential that the immune status of the recipient be known with absolute certainty. Reactivation of recipient HBV can occur with immunosuppression and some other treatments.

Matching the status will also include an assessment of the likelihood of transmitting viral phenotypes which may pose an additional hazard to the already-infected recipient including:

• viruses of increased pathogenicity
• drug resistant variants
• immune escape variants
• a number of co-infections such as hepatitis delta virus and herpes virus 8

Specialist microbiological or virological support should be sought at the earliest possible stage to ensure that appropriate testing has been undertaken in the correct manner and within the available time to inform the risk assessment and to confirm the recipient’s status.

Balancing risk and benefit

In general, derogation of the exclusion of infected donors should only be considered when the donation is truly considered to be life-preserving. In this situation the transplant clinician should, with the informed consent of the potential recipient, balance the risk of infection against the risk of dying while waiting for another graft.

Heart, lung and liver transplants will almost always fit within this definition, generally because the clinical situation of the recipient requiring these organs is likely to be one of incipient death. Other solid organs and some specialised tissues such as haematological stem cells may for individual recipients also fulfil this definition. Other tissues are unlikely to do so but exceptions may occur.

Where, however, short-term or intermediate support measures can be employed to avoid the immediate need for transplantation, and where there is a reasonable expectation of future availability of an appropriate organ, the balancing of risk and benefit may favour delaying the transplantation of a higher infection risk donation.

Risk mitigation

Specialist advice should be sought in order to aid decision making by the transplant surgeon and to inform discussions with the intended recipient in order to allow for informed consent. The nature of the specialist advice will depend on the infection risk but may include information on the following:

• risk of transmitting the infection
• possible prophylactic measure reducing the risk of transmission of infection
• monitoring for the recipient following transplant in order to determine whether the infection has been transmitted
• the risk of disease arising from the transmitted infection
• potential treatment options for the infection or the consequences of the infection
• outcomes related to the specific infection in the transplant setting

Prophylaxis for close contacts may include active immunisation, antimicrobial drugs and advice over the routes of transmission in order to reduce the risks of secondary transmission.

In the immediate post-transplant period comprehensive surveillance for infection of the recipient will be required with interventions planned should they become necessary in the face of active infection.

The offering, collection and use of organ donations carrying infection risks

Guidelines on the suitability for donation are issued by the Organ Donation and Transplantation directorate of NHS Blood and Transplant (NHSBT). However, where a potential donor is found by laboratory screening to be infected, or possibly be infected, with a pathogen, the specialist nurse organ donation (SNOD) should still consider offering life-preserving organs to the transplant community.

The decision to use such organs or tissues ultimately lies with the transplant surgeon and team and must only be taken with the express permission and informed consent of the recipient. If consent cannot be obtained from the individual undergoing transplant, then transplantation may be undertaken within the legal frameworks existing at that time, but it would be expected that the potential recipient’s next of kin would be involved in the discussions informing the decision-making process.

Discussions, decisions and consent must be recorded.

Expert microbiological advice should be sought and any recommendations recorded in the patient’s notes.

The retrieval team should be made aware of the potential hazards of organ retrieval where the donor is known to be infected, and appropriate control of infection procedures and risk reduction measures should be undertaken during organ retrieval. This may include appropriate personal protective equipment as required. Expert microbiological and infection control advice should be sought.

Any pre-transplant manipulation of the donation, either at the time of retrieval or at the time of transplantation must also be carried out observing the appropriate containment and risk reduction procedures relevant to the infection risk. They should include appropriate site terminal decontamination. Organs for transplantation taken from infected or potentially infected donors must be appropriately labelled for transplantation as normal, but in addition, where third-party contact with the donation could lead to a risk of infection, the external packaging should clearly be marked with ‘infection risk’ and carry the appropriate UN hazard labelling. Internal labelling must clearly state the nature of the infection risk.

See a list of all chapters in this guidance